Should job seekers contact hiring managers directly?

Most career advice says:

1. Find a job.

2. Apply online.

3. Wait.

But I've noticed that many candidates try a different approach: apply first, then send a short message directly to the person who likely owns the role.

Some people swear by it.

Others say it's annoying and hurts your chances.

I'm curious:

• Have you ever contacted a hiring manager directly?

• Did it help?

• If you're a manager, how do you feel about receiving these messages?

Interested to hear both sides.