Few years ago I got one, responded online and just told them I have ADHD and problems with authority. Never heard back.

Now if you paid me what I make by going to work id definitely have less problems with authority.

I got the letter in the mail the day before lockdown in 2020, so I had no one to talk to about it. I only found out later that they had moved jury trials to an auditorium in my city, but I never got a letter or could get a hold of anyone to tell me what to do. You are supposed to show up, by law employers need to give you the time off and you do get paid for showing up.

I was summoned once, was almost selected.

I got one, sort of. It was mailed to my parents house but I didn't live there at the time. I don't think I actually got it until after the "respond by" date, I was living 5 hours away and didn't visit very often

Is it also a criminal offense for failing to show up?

The times I was at jury selection, the judge issued warrants for the people who failed to appear.

is the probability on becoming part of the 12 jurors that high

I have been summoned 3 times (in my 60 years) , and was selected for a jury once.

I once received a summons I unintentionally ignored. I was working in a bush camp when it was sent and didn't actually get home to read it until almost six months later. Nothing ever came of it.

is the probability on becoming part of the 12 jurors that high?

You'll be in a pool of ~200 that gets whittled down to around 30. If you aren't selected and the reason isn't universally disqualifying you will go back into the pool for the next trial and so on for 2 years iirc.

Is it also a criminal offense for failing to show up?

Your jury notice(s) will make it explicit the consequences for dereliction of civic duty.

My partner was on a jury once.

I’ve never recorded a summons, nor anyone in my immediate family.

I got one and didn't go . nothing happened.