But no, the probability does decreases since not every ex-jailed becomes a repeated offender; also, some people die during the sentence... the probability does go down, for many small reasons compounded together.

Not unless I'm a robot programmed to prevent recidivism at all costs. Why are you even asking this?

> But no, the probability does decreases since not every ex-jailed becomes a repeated offender

...and not everyone released before their trial becomes a repeat offender.

> some people die during the sentence

Is that a significant effect? I don't think most sentences are long enough for that to make a big difference, and I don't think preventing a single crime per lifetime, at most, is enough reason to keep people locked up for the lengthy pre-trial process.