Why people think by reducing carb works?

Because whenever u are on carb-restriction diet. Your body will lose water weight. That's glycogen = energy. So whenever you're on those diet, you will lose weight fast for the first 2-weeks and then slowly reduce or plateau depending on how u diet/burn thereafter.

Many ppl mentally & physically weak at this point so what they do? They eat like mad carb-rich food and gained alot of water-weight back. So there goes CARB being labelled as the enemy.