Leaving the #gym without cooling down can leave you in a bad mental space. In a sweat sesh, your body releases the stress hormones adrenaline and cortisol. Without the #cool-down , you'll have a hard time properly returning to a balanced, relaxed state.
What's worse is that skipping your cooldown can get in the way of your weight-loss goals. Excess cortisol in your body slows your metabolism, hurts your weight goals, and keeps you up at night, in addition to many other negative side effects.
So do yourself a favor, don't skip your cool down. Work off the cortisol and keep feeling good after your workouts.