There comes a day in every non-technical entrepreneurs life when they ask their technical co-founder (or any software developer) for a time estimate.
The technical co-founder (or software developer) will ruminate for a few seconds, and then give an estimate that is more than a few hours.
The technical co-founder won’t go away and spent an half-hour thinking through all of the ramifications and how complex the yak will be to shave.
And it is at this point that you can safely ignore the estimate.
There’s no point pressing for a better estimate, or asking them to go away and think about the problem.
Your technical co-founder or software developer believes they are correct.
And that’s okay, because you need to learn to read estimates as much as your developer needs to learn how to give them.