Beyond Selidor

My one season and done (and thank goodness for that) show is Sharp Objects. When it was well-received, HBO wanted to renew it, but Amy Adams said no. Very glad for that.

Also! Cowboy Bebop (the original anime) was a single season, twenty-six eps. It's perfect.

For number three, while Amazon might renew Deadloch, the one season we've had is wonderful. I don't think I want more.

To round out the five things list (though these didn't stick to one season:)
American Vandal & Stranger Things