The more aggressive you play, the greater the chances of winning the hand. This is because aggressive players who can make their opponents fold when the pot is big and while they still have the best hand
These are the players who win battles here and there mostly by being lucky, but never win wars...
It comes from so called recreational players who never have anything real at stake, so they never really care whether they lose and how much...
Think in terms of war: snipers rule over everyone for well-known reasons; and an amateur with a gun shooting from behind a wall has much better chances against a pro with an assault rifle in open...
Being aggressive is being stupid, given no chance to higher brain to override your reptilian brain. Just one unjustified all-in makes you lose everything or too much to handle. When you rarely have something weighty at stake, it conditions your mind to take losses easy - to the point you start believing you're somewhat great, face real pro, who creatively make you raise and reraise, bet and rebet - till you committed almost everything, bluffed, and went home empty-handed...
Isn't if funny that it's often tight pros that encourage and lure novices to be aggressive as the way of playing - and it's much fun to see in tournaments how such folks eliminate each other with their all-ins, paving pros who just take time and enjoy the moment cloudless roads to final tables...
As I said, being aggressive is proudly demonstrating you're being stupid and enjoy being taken advantage - instead, in every play take calculated, justifiable, maximally-allowed or below risk.