Isn't 'No' one of the most important word in one's life? If you say 'No' at the right moment, at the right time... A small little two letter word can change your life. 'No' to someone whose taking advantage of you, 'No' to unhealthy food and overeating, 'No' to taking our environment lightly, 'No' to impulse buys (O.K at times they are good), 'No' to being overworked and overtired... the list goes on.
What happens when you 'No' a lot of time... I guess the biggest example is the number of times it is used in a child-parent relationship. While writing this I have said 'No' to Zoe 3-4 times... that is when I try to avoid using this word.
So if you can't say 'No' to your child what's the option? Talk to them, explain it to them and then the last resort might be a 'No'... Don't we all hate when we hear a 'No' to something we want desperately... kids are 'No' different.