When you are in the practice area, you should be coming up with the feel of the shot and deciding how to hit it.
Distance control is the final and most important skill you can develop for putting. You can't control distance without having solid ball roll, face hits, and speed.
If you are not confident in the shot you are making, you will not commit and will not hit a good shot. The first step to pre shot routine is choosing the shot you are comfortable with.
There is a line that separates practice and preparation from actually competing. Here are the two sides of the line.