HA! I love laning against top laners who beg for ganks. They are already tilted to the point where I can dive them for easy kills and when the jungler does come (if ever) its free gold. I especially love getting ganked by a level 2 lee sin 2 minutes into the game and getting first blood because my laner didnt follow up and help him.
But you have a point man. If you are a top laner who lost your lane, just fucking sit back and farm safely. You dont need to give the enemy teams Darius/Renekton/Fiora 10 kills in lane. And begging for ganks on a laner you fed will probably end poorly because they are strong enough to take on both you and the jungler by some point. Just sit back, farm, and if you get low on health, back off. No need sitting under your tower at 10% health because your fed laner will kill you. Yes, backing off may give them the tower for free but that gets them ahead and doesnt put you as far behind as dying again will. Much better to back buy and heal and hope your laner did the same since they get a free back as well.
The junglers job is to help the team how they see fit. If I see a skilled fiora top lane and Im the jungler, Ill gank her to get her rolling, then help the rest of my team and ignore top. If I see a god awful fizz mid, ill ignore him and spend my time helping players who can use my ganks effectively. The junglers job however, is not to babysit and win every lane. If you get ganked a lot, that means the enemy jungler sees you as an easy target. You are doing something wrong. Whether it be overextending, pushing to the enemy laners tower and harassing them there, using key abilities like dashing that you can use as an escape too frequently, or just being too aggressive. If you get ganked a lot, 9 times outta 10 its your fault. The other 1 time is either to camp a duo or to tilt a champ that has a reputation of tilting, like riven.
But please, if you gave your laner 5 free kills 10 minutes in, dont blame your jungler, it was most likely your fault. And asking for help will just put your jungler farther behind. Better it be just you whos behind than your teammates as well. Its a team game. Not everybody needs to be dominating to win. Skilled players can carry unskilled or behind players. Putting your team behind as well as you wont solve any problems.