My guess is that certain colors don't catch fish as well as others and in that sense colors may matter. But without the scientific method, who's to say for sure they don't work? I rarely use black, blue or grape for any soft plastic. Without trying them time and again in different lures used on different waters, I can't say they won't work. But that's no different than those that insist certain colors do work because fish were caught on certain colors given certain scenarios.