Consistency builds an audience. Repetition loses it. Between the two there is a line nobody points out, and you cross it without noticing, usually around the thirtieth post.
The advice you hear everywhere is "post three times a week". It is good, and incomplete. It handles frequency, which is easy, and leaves out variety, which is the actual work. Posting often with a single way of writing teaches your audience to skim you.
The sign that you have become predictable
It does not show up in the numbers straight away. Views hold, sometimes even climb; it is the comments that change in nature. They get short, approving, interchangeable. "So true." "Thanks for sharing."
That is the most reliable signal: your reader is no longer reading you, they are recognising you. They see your name, guess the angle, and approve without needing to reach the end. You have gained a habit and lost an attention.
"Another great post 👏"
Four things that can vary
Most people think they need to change subject. That is the least effective lever, and the most expensive: your subject is what makes you findable. There are four other variables, all easier to move.
A pace you can hold
Three posts a week held for six months beats five a week held for three. It is not a question of discipline but of reserves: writing fast burns through your examples first, and an author without examples falls back on generalities.
A simple signal that you are going too fast: if you catch yourself hunting for a subject the same morning, you are drawing on the generalities stock. Good posts almost always come from a note taken a few days earlier, in the moment.
On your own drafts, the review flags the techniques you are using. Finding the same hook three drafts running is the best warning you can get, before publishing rather than after.
The real risk
It is not tiring your audience. It is tiring yourself, then stopping abruptly after four months and concluding that "it doesn't work".
Consistency held over a long time is almost always the consequence of enjoyment, not of method. If you do not want to write the post, there is a fair chance nobody wants to read it, and that is the one indicator that cannot be gamed.