Chase the emails nobody answered

Following up is the least skilled work in a business and one of the most valuable. It fails for a boring reason: remembering who has not replied is a job nobody has, and by the time you notice, the moment has passed.

Decide what "no reply" means to you

This sounds pedantic and it decides everything.

A thread where they replied "thanks, looking now" has had a reply and still needs chasing. A thread where a colleague answered on your behalf has not been answered by the person you asked. Write down which of those you care about before you write the prompt, because the employee will follow whichever one you describe.

For most people the useful rule is: I sent something that asked for a decision or an action, and the person it was addressed to has not responded.

Set the cutoff by relationship, not by a number

Three days is not a rule, it is an average of situations that are not alike.

A warm prospect who asked for pricing should be chased sooner than a supplier you asked a routine question. Rather than one number, give the employee two or three bands and let it place each thread.

Write the job

Every weekday at 8am, look at mail I have sent in the last 21 days.

Find threads where I asked for a decision or an action from the person I
sent it to, and that person has not replied. A reply from someone else on
the thread does not count. An out-of-office does not count.

Chase on this timing:
  a customer or prospect        after 3 working days
  a supplier or partner         after 5 working days
  anything internal             after 2 working days

For each one, draft a short follow-up in the thread. Reference the specific
thing I asked for. Do not apologise for following up and do not say "just
circling back".

If a thread has already been chased twice with no reply, do not draft a
third. List it for me instead.

The last rule is the one that protects the relationship. An employee that follows up forever is worse than no follow-up at all, because it turns your name into something people learn to ignore. Two nudges and a human decision is roughly where politeness runs out.

Run it in draft for a fortnight

Leave the drafts in Gmail rather than sending. Every morning you will do about ninety seconds of reading, and you will find two things: threads it chased that were already resolved somewhere you could not see, and threads it missed because your first rule was too narrow.

Both are prompt edits, not reasons to stop.

Let it send the easy half

Once you have gone a week without correcting it, split the job: let it send the routine chases and hold anything involving money, a customer complaint, or a person it has already chased once. That split is where most people land and stay.

What good looks like

You stop discovering, three weeks later, that the thing you were waiting on was never going to arrive because nobody was ever asked twice.

The measure is not how many follow-ups went out. It is how many threads came back to life that you had already given up on.