Small locs on thin/medium hair
Ok, so your thinking of locing your hair and you are not sure of the size you should get, the first thing I woud say is to look at the thickness of your hair. Is your natural hair thin, thick? As a rule, if your natural hair is thin you would want to go with a smaller size loc pattern to give the illusion of fullness. Medium or thick hair can be loc'd in any size pattern, but know that with thicker hair, the smaller you go with you loc pattern the more work it will be to maintain them.
Big Dred Locs on thick hair
So with that said, should based on thickness and texture, Length is really a non factor and if anyone tells you that you need to cut your natural first to start locs, I would be suspect of there expertise, they just sound like a lazy loctician to me.
I love natural hair and Loc pictures and advice and I hope u do too. Thanks for reading and share your thoughts!