Equity isn't the chance of your hand getting better nor is it the chance of "winning" the pot.
When talking about equity, players usually refer to pot equity or fold equity.
Fold equity refers to how often your opponent will fold if you make certain moves such as re-raising their bet or
bluffing on the river. Fold equity raises when their are paired boards, straight draws, flush draws, A high boards with no betters, etc.
Pot equity refers to what percent of times would your hand need to win in this position for the move to be +EV. The more money in the pot and the smaller the action to you, the higher your pot equity will be thus meaning you have a better chance of the move being +EV even with fewer out to improve your hand.