If you're playing the same stakes all the time then create a bankroll that supports those stakes, and the swings of the game, then you should be able to play forever and make some money. Depending on your game.

If you want to increase your limits or the stakes your playing, then depositing additional money in your bankroll is one way to do it more quickly.

Alot of people don't want to go through the hassle of building $50 on micro tables to $500 for higher stakes play.

I wouldn't just deposit money into your online account monthly, like a mutual fund, though.