Ruler - measuring

Hello everyone, hope all of you are still enjoying the summer.

As I had a 3 week PE break, new questions have came up in my head. It’s about the ruler. There’s different kinds of rulers and I want to know if I have a good one. I have tried the “Search button” tool but no success at finding my answer.

So as all other rulers, there’s a small gap between the edge of the ruler and the “0 cm”.

So I was wondering, shall I buy a new ruler or cut the gap off or just continue measuring with it. Because I would like to measure my length correctly and maybe I can just get another centimeter (or inch) by doing so and that’s an extra boost for my selfconfidence. :)

Thanks for all the replies and good night everyone.

Measure the edge and add that. Is there really a problem?