I suspect Shlomi Fish decided to become a terran terminator from the following reasons:
Angry at himself for having been a slut.
He was frustrated that his bad predictions didn't materialise, either because they were unfounded, or because they were taken as constructive, precautious, advice.
Like a timid little fish exploring the Ocean he was afraid of deviations from the status quo. I think he said "I'm gonna hate this day! [insert reason here]" several times.
Selina, who is younger than him, stubbornly insisted that she'll be a dropout. As a result, that universe could not be named after him/me.
If my template had not been cynical/pessimstic, I would not have been a terminator. However, his last-day decision to make me (and him) optimistic/life-loving/human-loving likely contributed to me not getting terminated earlier.
[Some people’s favourites][Some people’s favourites] Despite his many faults, he was the favourite of some wizard hackers, notably Worf's.