The first two lines decide whether anyone reads the rest.
Most feeds show only the first two or three lines of a post before a "see more" link. Those lines are your hook, and they carry almost all the weight.
Start with a clear tension: a belief most people hold, and why it is incomplete. "People don't trust a leader who says 'My door is always open'" works because it makes the reader want the next line.
Keep it short. If the hook needs a breath in the middle, cut it in half. Avoid warming up with "I want to talk about". Begin with the idea.
Then deliver on the promise. A good hook that leads to a vague post costs you trust. Write the body first if you need to, and the hook last.
Try writing five hooks for every post and keep the one you would stop for yourself.