Most build in public accounts fail the same way. They start as a commitment to transparency and become a log.
Day 17. Worked on the backend. Feeling motivated.
Nothing there is false. Nothing there is worth reading either. The author has confused posting frequently with posting something.
The difference
A diary entry records that time passed. An update gives the reader a reason to care.
Compare:
Day 17. Reworked the data model.
with:
Day 17: I changed the data model because the original structure made one workflow unnecessarily hard. Here is the tradeoff I took.
Same day, same work. The second one contains a decision, a reason, and something transferable. Someone who will never use your product can still take something from it.
That is the bar. Not "did I write something" but "does this give the reader anything".
Three things that make an update worth reading
A decision. You chose between two things. Say which, and why. Decisions are interesting even when the subject is not, because the reasoning transfers.
A surprise. Something took longer than expected, or turned out easier, or worked differently than you assumed. Surprise is the most reliable source of interest, because it is the part the reader could not have predicted.
A specific. One concrete detail beats three general claims. "Firestore plus a scheduled function" beats "a modern backend". "Four hours on one line" beats "spent a while debugging".
If an update has none of the three, it is a diary entry. That does not mean do not write it. It means do not post it.
The unit is not the day
The other mistake is letting the calendar decide what a post is about.
You did not do one thing on Tuesday. You did six, and four of them were routine. A post about Tuesday is a post about six things, which is a post about nothing.
The unit that works is the piece of work, not the day. Shipping CSV export might take four days and produce one post. A single afternoon might contain three separate things worth saying and none of them are "here is my Wednesday".
This is worth being deliberate about because the calendar is the default. Posting daily makes the day the unit by accident.
You do not owe anyone completeness
A related trap: the sense that if you are building in public, you have to report everything.
You do not. Nobody is auditing you. The only obligation is that what you do say is true.
Skipping the boring parts is not dishonest, it is editing. An account that posts only the interesting third of the work is a better account than one that posts all of it, and the reader gets the same underlying story.
The test
Before posting, ask whether a stranger with no interest in your product would get anything from it.
If the answer is no, the post is for you, not for them. Which is fine. Keep a real journal for that. It is a good habit and it has nothing to do with what you publish.