The art of Gank

When I play jungle I usually don't gank the lanes that are pushed, especially during early game. It's pointless because towerdiving early doesn't end well and ganking at the enemy who is very close to tower is just a waste of time, it just can't be succesful (ofc assuming that enemy isn't a total noob). But when my teammate is pushing, that means that enemy jungler is in good position to gank. And if he is doing it right and my ally didn't ward himself (or he is not paying attention to the mini map because I always ward mid and solo lane when I'm jungling)then the gank is succesful. Of course after some deads my allies starts to complain about me, that I'm terrible jungler and I'm not ganking their lane...

The question is, Am I doing it wrong? Maybe I should change playstyle a little bit and start to gank even pushed lanes? How and when do You think jungler should gank?

No, you are not wrong. If your lane is pushing, they should ward. It's a basic principle.

Of course, that depends on how powerful you are. If you are someone like Arachne who can pull a defender out of a tower, you might be able to see why your team is angry at how you can fix their problem but you do not.

But still, erring on the side of caution is rarely wrong.

I've never played Arachne jungle. I know that Fenrir (that's my favourite jungler at the moment) can towerdive realy good with his ult but still if enemy is not low on health he will probably survive that even if You follow with brutalize... Of course it can be succesful if Your mid follows You but relying on Your partners to follow You during a gank in casual is just risky :P

I only jump if their near death. Talking red level here. Seeing that a lot of junglers have good tower dive Ults or abilities.

I know many may say that I'm pretty much kill stealing but on average I do it for gods who don't have a good tower dive ability or are really squishy.

But I'm not going to dive when the enemy is still in the yellow. Too much risk for very little reward.