Of course, you learn long strokes not because they look pretty, but because they work better. When you poke at the ball, your racquet is in the process of decelerating when it meets the ball. This makes it unstable, and the result is an unpredictable racquet angle that can send the ball all over the place.
In addition, short, pokey strokes generally don't produce any topspin, which is the best tool for consistency, and they don't generate any pace. Failing to generate good offense is a great risk in itself, because you prolong points you should have already won. You'll have no offense with pokey strokes.
2. Getting caught in "No Person's Land": When you move inside your baseline to get a ball, you have to either get back behind your baseline or move to the net right away. From inside the area between the baseline and the service line, you can't volley effectively, and any ball that lands behind you won't be playable with a groundstroke. If you're good at the net, move forward whenever you can hit a strong approach shot. If not, learn to backpedal quickly, but still go to net if you don't have time to get all the way back before it's time to hit the next ball. You don't want to get caught retreating when the ball arrives.