Is it necessary?

[Menoko]

I have learned piano for nearly one year and now is
playing 849. My teacher requires me to play every piece
without any stop. I found it is really hard for a beginner to do so. Even after several weeks practicing, I also can not play it without any stop. Should I keep on practicing this piece until I can play it without any stop or go to the next piece? Maybe after weeks when I play this piece again I can play it better.
I wonder how your teacher require you when you are a beginner?
Thank you!

[xvimbi]

What do you mean "without any stops"? It could mean that your teacher wants you to get you to a state with your pieces where you could perform them. I think that is a reasonable goal. However, one often studies a piece only because of a small number of aspects (often only a single aspect, say a trill). in that case, it might be acceptable to move on to the next piece as soon as this aspect has been comprehended and mastered.

On the other hand, your teacher may just encourage you to play through mistakes. Some people stop at the first mistake and then start from the beginning again. This way, one will never play the piece in it's entirety, so the beginning gets practiced a lot, whereas the end does not.