I kinda agree with the others. Some guys *always* go for spawncamping, even in high ranks sometimes. But if you don't care about how the game is going on, there is a good chance you'll make your team lose, even if you end up with a 10/2 ratio or so. I'm pretty sure some guys are blaming their teams for being bad, juste because they have the best ratio from this "strategy", but in the end they are the one to blame for a good number of their defeats.
I'd like to add that in a team, it's good to have several roles. So, if your team already has one very aggressive player trying to spawncamp, it's better to play the objective than just trying to pick some more kills. As it's good to try a flanking strategy when your whole team is quite passive, waiting for a chance to push the objective.
In any case, if you're in solo, I would advise adapting to your teammates. If you want to rank up, the most flexible weapons are the easy way, though if you want to have fun any weapon can do the trick, even if it means losing a bit more often.