If a player turns red in an area, I set it to zero, and put them in skills that are still black or blue. If I have a player with lots of potential in lots of areas, I might even go with zero in a skill that is low, that is not important. For example if a PG can improve in lots of areas, and is blue in BH and Passing, but is black with 12 in rebounding, I'll probably make rebounding zero until late in his career after I have maxed out other areas.