Why do people tell lies? 
I think people tell lies because they are very unhappy and sad about themselves, and not realizing they tell more lies to cover up the previous ones. Even "little white lies" to spare the feelings of others at times is still fibbing , sad but true in my opinion , I have told little white lies to cheer some others up , feel guilty , but oh well....
I have told little white lies also as I didn't want to make a person feel sad. It's the ones that make you ask yourself when the truth does come out that yourself did you actually know this person at all .
Question was why do PPL lie,
Insecurity, co-dependecy, fear,
and loads more, Plus some are just Bad ass anyway.
I believe partly that people tell lies also rely on their fear, they don't want to tell the truth because they are afraid someone will get hurt.
Well, I guess all the answers touch on the reason why people lie. But what I find really interesting are people when asked if they lie, excuse it or are offended by the question. To lie for any reason still makes it a lie. I love those people that lie by omission. They feel they beat the game. And honestly feel they don't lie.
Bottom line. There are as many reasons people lie as grains of sand on a beach. Pick you poison.
I just think there is a huge difference between little white lies and the big ones that can actually make you feel ill