The answer is very relative. Tournaments have a lot of variance so you need some good luck as well as making good decisions to survive in them, especially with the standard starting stack in online tournies. However, they are nearly risk-free since you are only losing your buy in. Also tournies are for people who like playing long hours and are ready to bust out before the money and not go on tilt after playing long hours. Cash games on the other hand are much more proffitable, involve more skill, less variance but more, much more risk. When you lose to a bad beat you might lose all your money. However, with descent strategy and playing tight, it is very unlikely that you will lose more than 200-300BB - Although people keep saying you should have 20 buy ins but from my experience, I've never lost more than 200-300BB. If you wanna play loose then yea you might lose 300+BB but playing tight, you are pretty safe in my opinion Also, most important difference is
bankroll - you need, IN MY OPINION, although im sure many people will dispute it, 300-400BB for each table you play on so if you multi table on 4 tables, then you need around 16 buy ins. Ofcourse, im talking about low stakes (maximum being $1 BB) and at higher stakes I don't know how much bankroll you need in proportion to your buy ins because the higher you go, the more agressive people will be and you will have to make risky calls in order to not be bluffed every single time.. if you watch the high stakes tables, they are truly a joke with people pushing literally with mid pairs (mike matusow) etc etc because of how much people
bluff.