As you focus on making or missing your par, birdie, bogie or whatever, this causes you to forget about execution and lose sight of what it takes to hit a solid putt. If you engage in wishy-washy putting you have trouble making decisions. You change you mind often about how you want to hit your putt. You read your putt and pick a line, but then change your mind as you stand over the ball. You have two lines in your mind, which causes doubt.
Indecision kills a smooth stroke.
Indecision and doubt are a putter's worst enemy. If you engage in panicked putting, you are too scared to pull the putter back. You panic because putting is the weakest part of your game and you know it. You know that if you are going to score well, you need to make putts. Visions of poor putting rounds and missed putts has you bewildered.