Intensity is also important. One symptom of autism for me is compulsive tendencies. The things on the shelf have a correct order and it bothers me if they aren't in that order. Food has a correct order to eat it in and I don't go back and forth between things or mix things together. Various daily tasks have to be done in a certain order.

I don't have OCD. The difference is that I can still function if these things are done wrong, it causes anxiety and agitation but not beyond a level that I can deal with. Someone with OCD might have the exact same tendencies but not be able to move forward without "fixing" whatever is wrong even if fixing it causes them injury or prevents them from dealing with more important things. Everyone wants to wash their hands sometimes. People without strong compulsions stop before their hands bleed.