Email List Health Before Black Friday: What to Check, an interview with Radek Kaczyński, Bouncer CEO

Monica Badiu, Email Copywriter & Copy Coach

Email List Health Before Black Friday: What to Check, an interview with Radek Kaczyński, Bouncer CEO

Estimated reading time: 11 minutes

A database of 20,000 contacts can look like a promising audience for a Black Friday campaign, but the number doesn’t tell you whether those addresses are still valid, if the people remember you, or how and when they expect to hear from you.

These are the questions you should be asking if you’ve been sending inconsistently throughout the year and now you’re preparing to amp up frequency for Black Friday. Adding more promotional emails can expose problems that were less visible while you were sending irregularly. It can also leave you trying to figure out delivery issues in the middle of the campaign you have spent weeks preparing for AND one that has a significant revenue impact.

On this episode of Master The Inbox, I spoke with Radek Kaczyński, CEO of Bouncer, about checking your email list health before Black Friday. We started with a real course-creator scenario: 20,000 contacts, irregular sending, little segmentation, and a plan to email everyone more often in November.

Listen to the full conversation with Radek Kaczyński on Apple Podcasts, Spotify.

Timestamp

00:00 — Is your list ready for Black Friday?
02:00 — Three risks in a 20,000-contact campaign plan
05:00 — Bouncer’s own deliverability setback
08:00 — The service-counter problem that led to Bouncer
16:00 — Why addresses become invalid or risky
24:00 — Bounce rates and what to do when they rise
33:00 — What verification adds to your email platform
40:00 — Older segments, re-engagement and quiet customers
46:00 — Verification versus double opt-in
53:00 — Bouncer and the listener offer

What You’ll Learn in This Episode

List quality, sending consistency, and engagement are separate issues to review before increasing promotional emails.
An address can be incorrect when someone signs up or become unusable later as their circumstances change.
Verification can provide information before sending; bounce reports show what happened when a delivery was attempted.
Rising bounce rates deserve investigation, and acceptable limits and enforcement vary between email providers.
Older segments may need technical checks and a careful re-engagement plan before they join a promotion.
Low email engagement doesn’t describe every aspect of a customer relationship; purchase history and other relevant signals add context.
Verification and double opt-in serve different purposes and can complement one another.
Deliverability recovery can take time: Radek says Bouncer’s own problem took about six months to stabilise.

Check your list with Bouncer:

Master The Inbox listeners get 20% off a first purchase with this link OR contact the website chat and mention that you came from Monica and Master The Inbox.

List quality, sending consistency, and engagement need separate attention

Radek identified three concerns in that scenario:

First, some addresses may no longer be usable.
Second, the sender’s new volume and frequency may differ sharply from their previous behaviour.
Third, recipients may not remember the business or want the extra messages.

These issues overlap, but checking one doesn’t resolve the others. Verifying addresses doesn’t establish that people want your promotion or sending useful content doesn’t correct an address that was entered incorrectly. Having permission to email someone doesn’t guarantee that their mailbox still exists.

Start by looking at the audience you intend to contact and comparing it with the audience you have been contacting regularly. An older segment that has received nothing for months needs a different assessment from customers who interact with you every week.

Google’s sender guidance supports starting with a low volume to engaged users, increasing gradually, and monitoring delivery signals as volume changes. It also recommends consistent sending rather than bursts. Those are useful principles when you plan how to return to a disengaged audience. Read Google’s email sender guidelines.

A deliverability setback can affect more than one campaign

Radek shared that Bouncer had experienced its own deliverability problem before Q4. He said it affected revenue and took around six months to stabilise. That is his account of one business’s experience, rather than a forecast for how long another sender’s recovery will take.

I had a different experience that introduced me to deliverability.

A course creator I was working with seemed to have a strong list. I didn’t have access to inspect the email platform, so I planned from those numbers. After a very energy-consuming campaign, the results didn’t match what the reported audience and benchmarks had led me to expect.

Part of the problem was that the apparent audience included email addresses that no longer functioned. The headline list size had concealed a more basic question about who we could reach.

For your next campaign, ask to see more than the total contact count. Review recent sends, failures, suppressions, and the history of the segment you want to include. That gives you a better starting point for both planning and expectations.

Radek’s route into verification began outside the marketing industry. Working in IT for a truck manufacturer, he saw how email addresses entered at service counters could be captured incorrectly. A truck driver might spell out a fleet manager’s address, and a mistake would interrupt communication with the person making a decision.

That problem extended into later contact, including customer follow-up. It helped inspire the business he would build after returning to Poland.

For a course creator, the entry point may be a webinar form or a lead magnet rather than a service counter. The underlying problem is similar: if the address is wrong, the intended conversation can fail before the first useful message arrives.

Some addresses become unusable over time: people change jobs, leave organisations, or stop using old accounts.

A record that was valid when collected should not be treated as permanently reliable just because it remains in your platform.

Look at both ends of the process: make it easy for people to enter accurate information, and review older data before including it in a major send. These are different opportunities to improve the quality of the audience you can contact.

Verification gives information before a send, but it has limits

Your email platform can record delivery failures after an email is attempted. Verification aims to provide information about addresses before you send the campaign.

Radek explains that Bouncer checks addresses without delivering a campaign email to them.

That timing is useful when considering a segment you haven’t contacted for a long time. You may not have recent bounce information because you haven’t made any recent delivery attempts and no recorded failure during that period doesn’t prove the addresses are current.

Verification results also need interpretation. In the conversation, Radek discusses deliverable, undeliverable, risky, and unknown results, along with additional risk information. Uncertainty should remain visible rather than being treated as a definite yes or no.

A verification service cannot guarantee inbox placement, confirm that every recipient wants your content, or identify every possible spam trap. Radek explicitly acknowledges that no one knows all spam traps. Use verification as one input into a sending decision, alongside permission, recent activity, and your provider’s guidance.

Investigate rising bounces instead of pressing on with the campaign

I asked Radek what he would do if someone resumed sending after a long gap and saw higher bounces alongside lower opens. His first recommendation was to pause and review the situation rather than continuing at the same pace.

The practical work starts with what your platform reports.

Check the failure reasons and whether permanently failed addresses have already been suppressed.
Review the audience still eligible to receive the remaining messages. If you need help interpreting the issue, speak with your provider before resuming a larger send.

Radek discusses example bounce-rate ranges in the episode, but those numbers should not become a universal target or permission to keep sending until you reach a threshold. Providers have different policies, and the cause of the failures matters. A change from your own usual results is worth understanding.

Keep different measurements separate:

A bounce rate describes delivery attempts that failed.
A spam complaint describes a recipient marking a message as spam.
They have different meanings and should not be compared as though they were the same metric.

Google Postmaster Tools is one monitoring resource discussed in the episode. Check what data is available for your domain and sending volume; don’t assume every sender will see every report or a complete historical picture immediately.

Older segments need a reason to rejoin the conversation

One useful distinction in the interview concerns contacts that remain in the database but sit outside regular sends. A business may be communicating consistently with its active audience while having very little current information about an older group.

If you’re considering reconnecting with that group, first check whether you still have an appropriate basis to contact them and whether you previously promised to stop. Verification doesn’t override an unsubscribe or restore withdrawn permission.

For an eligible older segment, address checks are only part of preparation. People may also need a reminder of who you are, why they joined, and what they can expect now. A sudden high-frequency sales campaign asks them to resume a relationship on your timetable.

Give re-engagement its own purpose. Find out what remains relevant, offer clear preferences, and observe the response before deciding on a larger promotion. A valid address can belong to someone who no longer wants the original topic.

The related episode, Email Re-engagement Strategies Ahead of Black Friday, explores those subscriber questions in more detail. Find it in the Master The Inbox Black Friday season.

Disengaged readers can still be customers

Radek also brought up something that many marketers find frustratingly familiar. He sometimes deletes emails without opening them because he wants to keep his inbox manageable. Yet he may still like the brand, buy from it occasionally, and hope to receive a relevant offer.

So what does that tell you? It doesn’t mean every disengaged address is equally disengaged. It means open and click reports don’t describe the entire customer relationship and you should take into account purchase history and other relevant, appropriately collected activity.

In the conversation, I describe using a shorter promotional approach for selected audiences, along with an option to skip the campaign. That is a strategy for a particular segment, not a reason to send every dormant contact the same sequence.

Consider the evidence you have about the person, rather than treating one behaviour as the whole story. Then make it easy for them to tell you whether they want the additional messages. An unsubscribe is a clearer expression of preference than trying to infer interest indefinitely.

Verification and double opt-in answer different questions

Verification at signup can help identify a potentially incorrect address while the person is still completing the form. That creates an opportunity to ask them to correct a typo rather than discovering the problem after they have left.

Double opt-in adds a confirmation step through the mailbox. It helps establish that someone with access to the address is confirming the subscription. Verification alone does not provide that confirmation or prove the owner’s consent.

This distinction matters because a perfectly valid address could belong to someone other than the person typing it into your form. An address can pass a technical check while the intended recipient knows nothing about the signup.

Review what each step in your signup process actually does.
Where verification is available, decide how you will handle uncertain results and correction prompts.
Where confirmation is required by your process, keep that step meaningful.
Neither mechanism replaces the need to respect the person’s preferences after signup.

What to do this week

Before increasing your Black Friday sends, work through these four checks:

Identify the audience you are adding. Separate regularly contacted subscribers from older groups you are considering reintroducing.
Review permission and address information. Honour existing suppressions, investigate old data, and decide where verification would provide information you don’t already have.
Plan a gradual return to sending. Start from the audience most likely to expect your messages, monitor the response, and avoid treating technical verification as a reason for an immediate full-list promotion.
Check the signup experience. Make address entry clear and understand the separate jobs of verification, confirmation, and preference management.

For a 10-minute starting point, choose one old segment and check when it last received email. Note what you know about its permission, recent customer activity, and address quality. The gaps will help you decide what to investigate before writing to it.

The goal is to plan around an audience you understand. A large contact count can support a campaign only when the underlying data and customer relationships support the messages you intend to send.

Listen to the full conversation with Radek Kaczyński on Apple Podcasts, Spotify.

Check your list with Bouncer:

Master The Inbox listeners get 20% off a first purchase with this link OR contact the website chat and mention that you came from Monica and Master The Inbox.