After careful consideration, I think the main reason to build anything adjustable is if you want to sell it. That makes sense: the buyer can customize it to his or her needs. But if I am making something for myself, I am going with fixed components and shelves. Whats more custom than that?
This is version 2.0 of my silverware organizer. It took me a while to use my old one before I figured out how to improve it. Having adjustable dividers was my biggest mistake on the beta version.