How to write a LinkedIn hook that isn't a trick
The fold is about 210 characters. Most advice tells you to exploit it. Here's how to earn it instead.
LinkedIn shows roughly the first 210 characters, or about three lines, before it cuts you off with a "see more". Everything you have ever been told about hooks descends from that one fact.
Which is why most hook advice is really manipulation advice. Open a loop. Withhold the payoff. Make them click. It works, briefly, and then it does not, because your audience learns that your loops close on nothing.
The two-part test
A hook has exactly two jobs, and they pull against each other:
Earn the click. Give a reason to expand.
Deserve it. What's underneath has to be at least as good as what you promised.
Most advice covers the first and ignores the second, and the second is the one that compounds. Break it and the next hook works less well, forever.
What actually earns an expand
A specific number that implies a story. "We lost two clients in eighteen months after cutting half our services" works because the number is odd enough to be real and the sentence implies a decision worth hearing about.
A stated position someone could argue with. "B2B buyers don't make vendor decisions on Instagram" invites disagreement, and disagreement is engagement that does not require a trick.
An admission that costs you something. Not manufactured vulnerability, which everyone can smell. An actual mistake with an actual consequence.
What doesn't
"Here's what I learned." Learned what? You have said nothing.
"Most people get this wrong." Which people? Which thing?
"Unpopular opinion:" followed by an entirely popular opinion.
A question you don't actually want answered.
If your hook would work equally well on top of a different post, it is not a hook. It is a label.
The practical move
Write the post first, hook last. The hook is almost always already in there — usually the most specific sentence in the third paragraph, the one you wrote without thinking because it was just what happened. Cut it, put it on top, and delete the throat-clearing it used to sit behind.