Strictly speaking it is not necessary to put the title first. Google when evaluating URL's and pages work from left to right and up to down. In other words if the category is first and then the page title Google may rank the category as a higher keyword than the title but this is not necessarily a bad thing depending on your use case.
Based on the most generic definition a category should be a logical grouping of similar subject matter articles and as such you may feel that the category is an important keyword.
Basically though a good rule of thumb to follow is to make sure your URL's are well structured, meaningful to the end user, and follow some sort of common scheme for your site.