To win at poker you don’t have to be best in the world, you just have to better than your opponents. The same thing goes for your table. You don’t have to be better than everyone, but if you’re the worst player at the table you’re going to lose.
Most of your profits will come from the worst couple players at the table so you have to be able to identify the weak spots and focus on playing as many pots against them as possible.
You also have to be honest with yourself and be able to see when you’re the weak spot at the table. Don’t let your ego get in the way. Just pick up your chips and find a game where you’re not the mark.