I think there are so many factors that it is almost impossible to nail it down to a clear cut formula. Species tendencies and level of competition from other fish play a very large role I think. For example a small pond with lots of small bass that are competing for food you will usually catch more on bright easily seen colors no matter what the conditions. Maybe this is because they see the other fish going for the bait at the same time they are and it is an eat or starve scenario. Then in a similar sized pond with abundant forage where there are very few bass they will get very picky about color and bait. I read a study a while back that showed fish population does not relate to fishing success. It is theorized that catch rates in lakes are based more on prey availability than gamefish population. The more food there is the less likely the fish are to bite.
So the reason why some colors work or fail on any given day may be affected by factors like... are the fish are even hungry or will you need to get a reaction strike, are they part of a school or just scattered loners, and are there massive amounts of prey around that you need your bait to stand out from, or do you want to match the hatch. There are so many factors that it is easy to think yourself into circles. Also as was mentioned earlier different spots on the lake will like different colors and presentations. A school of bass on a point busting a school of shad will want something different than the a bass on a stump up on the bank.
For me there are three decisions when choosing a color, Light or dark, flash or no flash, natural earthy hue or unnatural fluorescent hue.
making color changes based on these 3 variables helps me to feel like I know why im changing colors and what other colors might work as well or better than what im currently using.
I do love to discuss it because when you find that one awesome color of the moment and nothing else is working its an amazing thing. It seems to me though that we will never know for sure why it happens that way sometimes.
