I've i've never riden before, i automatically go to the back... Unless the front is randomly free, in which i take the unusual opotunity of no extra waiting time.
However, as you get to know coasters you get to know where they perform best. And a lot of the time, it isn't at the back.
Inferno, for example, is much better towards the front. Ultimate and PMBO are better in the front carriage.
Some coasters are visually better at the front... Colossus almost becomes good.
And then, classically, the back perfroms best. So usually i go for the back, but that's more of a queue thing than anything else. "Next best option" type thing.