Nothing succeeds like success, they say. If you succeed once, you find that succeeding again is easier. This is because success is a great motivator. Success creates immense confidence you. 'You have made it once. So, you can make it again and you can make it any number of times' is the message subconsciously generated at a time you achieve success. Since confidence is a powerful driving force, you will find it easier to accomplish more.
The reverse happens when you fail. Failure erodes your confidence and intensifies your fears. You will be liable to think that you will fail again. So, when you try to do the same thing again or a new thing, the fear of failure can trip your chances of success. A repeat failure will intensify the fear of failure and will create a failure syndrome.
So, how do we react to failure? The most common way people react to failure is to avoid trying. If I don't try, I can't fail. Therefore not trying and thus avoiding failure seems better than trying and failing. Thus failure also motivates people in a negative way. It motivates you to avoid doing things that you fear. You will be surprised to know that a large number of people give up their efforts to learn driving a scooter if they fall down once. Same is the case with car driving. They rationalize their avoidance by inventing reasons like it is cheaper to hire a cab whenever you need than to own a car.
People take a lot of care to avoid doing the things they fear. A student who fails in a test once will invent reasons for not taking up the test again. People will send money and keep themselves far away to avoid a public speaking obligation. Well, you can find out examples from your own life about the occasions when you have avoided failure.
So there is a success motivation and a failure avoidance motivation, the latter being much stronger than the former!