"i only gank winning lanes"
that is the STUPIDEST thing i hear junglers say.
winning lanes don't NEED your help. because they're winning. if you're gonna do and say that, then don't get mad when someone who is outmatched in lane loses. part of jungling is going where you're NEEDED. i don't expect you to win people's lanes for them, but you can't be mad at someone if they're losing lane and you just outright refuse to gank for them. especially if they're seeing a lot of enemy jungle pressure too.
good junglers are equalizers. when a lane is behind they go in, help get the lane even, then go where ever else they're needed.
nothing sets me off more than when a jungler sits there and rages at someone who lost lane, and then their retort to them never ganking is "i don't gank losing lanes". if that's the case then shut the hell up because you're not doing what any competent jungler does.
i jungle. and the one thing i know for a fact is that if i see a lane get behind, i focus on that lane so they don't become even more of a liability endgame.