Believe it or not, doubt has its place. You might be asking how this is possible (or how much I have been drinking). But it is true, doubt has a proper place in our lives. You see, it is all in how we use it.
One of the problems with doubt (like too many things) is that it does not come with an instruction manual. And in that, most people use it incorrectly. You see, we use doubt to hamper belief in ourselves. We doubt that we can do something. We doubt if we are good enough. We doubt that we can succeed. This is totally the wrong approach.
The way to use doubt is completely opposite to how we have been using it. To use it properly, we need to use it to bolster us up, not down. We need to affect the outcome so that it is in a positive nature, not negative.
When we start something, and doubt creeps in, we usually doubt that we can succeed. But we need to doubt that we CAN'T succeed, or in other word doubt that we can fail. If you doubt that you can fail, you open up to the probability of succeeding, in fact, you make it possible to succeed. You make that success guaranteed. That is called putting all your faith and belief into yourself to make that outcome happen. That is tapping into your inner strength and pushing forward with everything you have and making a success.
Basically, rather than doubting your success, doubt your failure. I am starting a project, and I doubt that I will fail. That opens the path for me to succeed.
So doubt has its place as long as you use it properly.