In a world far, far, far away...well actually, quite close by...in my imgination, it can :-)
However, an easy, peasy quick-fix-it like a Magic Eraser isn't always handy. So like untended dirt and grime, doubt can build up. Over time, this doubt can fester and I think it's fair to say that festering's not a good thing. If you have a dream, this doubt can make it an impossibility through your own self-prophesy.
For instance, if I walk around saying, "I'll never be a professional writer," then how can I expect otherwise when I give doubt so much power over what I say, I do, I dream or desire to accomplish? I become my own worst enemy.
So what's a gal to do? What is anybody to do? First and foremost, take a moment and be honest with yourself. Are you a pessimist with no hope of thinking anything good can come of your life? Are you a realist - like me - occassionally stuck on the realities of this not-so-perfect world? Perhaps you're an optimist too caught up on how green the grass is that you don't see the ground coming at you as break-neck speeds because you refuse to acknowledge that you slipped from your perch high up in the clouds? Whatever method gets you to a point that doubt finds an entry into your mind, face it. This will make it easier to deal with doubt the best way for you.
After doing the hardest part of all, being honest with yourself, the work can begin to overcome those doubts. If we were light bulbs instead of humans, this could be done with the flick of a switch. Doubt. No doubt. Doubt. No doubt. However...that isn't the case. Our minds waunder, linger, hold on to memories and emotions with a vise grip. When doubt festers, it becomes more a part of you than you know. You can speak it without realizing it. One way I am working on overcoming my own doubts is working on my words. I am a writer and with work, I can make writing my profession and not just a passion I see to on occassion.
I. Am. A. Writer. And I am an overcomer of doubts.