>I might be misinformed, but I imagine that people only plead if they think it’s a good deal for them, like any other negotiation.

>“If we go to trial and convict you, you’ll get 10 years. But if you plead guilty today, we’ll agree to give you 5 years.”

>I can’t imagine anyone would plead guilty and accept the whole 10 years. That’s just not logical.

>Good deal for the suspect. And the prosecutor gets to do less work. But not a good deal for society.

Yes, but also no. A trial is unpredictable. The defendant doesn't want a trial because there's a chance they'll get the max. The prosecutor doesn't want a trial because the defendant might walk. The lawyers on both sides are guessing at the probability of every outcome and bargaining. That's most of the job these days.

>If there’s enough evidence for a conviction, maybe it’s about time we start getting convictions and some real sentences.

That's the other sticky thing. The jury is not always making a clear factual determination. You're asking a group of twelve amateurs to come to a consensus about some big gray areas, e.g. intent.