Validating an input field while it's still focused is like a teacher repeatedly interjecting "this is no complete sentence" before the students have finished their sentence.

I couldn't agree more!

I'm disappointed this rant didn't finish half

field being in focus doesn't mean I'm not done. field not being in focus doesn't mean I'm done.

focus alone is a very bad criterium

I hate when they don’t give instructions on how to format and leave you guessing

What is you want to send on pressing 'return/enter' young man. That big button.

Well yeah, gotta make sure that users are stressed as much as possible. Just add a slow and cpu intensive validation to make the input feel janky.

Then add confusing error messages and just for fun add an A/B test on the form that is broken half the time.

Bonus points if you "forget" to add any useful contact information to your website/app.

Just give the address of some remote island.

It's very typical of UI designer these days. Not only they perform task on each key press (inside an input field), they even remove the submit button.

@daniel-wu

No submit/validate/save button is the death of me.