On plans, maps, and engineering drawings it means that you should not measure a length on the document and then expect to be able to calculate the “real life” distance from it.

Does not scale well meaning?

If something “scales well”, it means that it continues to work well when it is made bigger. However, if problems grow along with the business then that is never good.

What is to scale mean?

phrase. If the different parts of a map, drawing, or model are to scale, they are the right size in relation to each other.

A. A phrase that means at the required size to solve the problem. At scale typically refers to handling larger volumes.