This is what practice looks like. Falling over, modifications (holding my other foot out), and barely completing 5 reps. But you can be damn sure I will be able to do a full pistol squat in no time because I will keep practicing this movement and getting better and better. Remember, working out is just like anything else. You may not be "good" at it at first, but over time with some dedication and practice, you'll be amazed at the things your body and mind can accomplish. Get after it!