I tend to not pay that much attention to mechanics when I make decisions about my character. I also don't spend very much, if any, time thinking through my character's "progression" at chargen. I'll let those things develop organically. Note, I am also playing Basic/OSE. Its not something as easily ignored in 5e, but I can't honestly be bothered to try to get into the inner workings of maximizing my (or any) character, its not in my nature.
Another player in our group is the complete opposite. Its all maximization and all planned out in advance, and RP is a tertiary or worse consideration, with no other considerations in between other that moar power and moar magic items. He also sees the game as "winnable" and is always out to beat the DM and the other players.
And before anyone says anything, I am not positing that these are the only two points - RP v maximizing. These happen to be two situations I find in my group, with different levels in between and further along the continuum. As usual, YMMV.