As with any other lure, I’d be willing to bet that the main criteria you use when choosing a soft plastic is color and action. It makes sense, but how often do you factor in bottom content when rifling through your box for something rubber? You don’t need me to tell you that the different types of bottom a bass angler encounters varies from hard as a rock (literally) to as soft as bowl of pudding. Then you have to throw variables like density, consistency, and aquatic vegetation into the mix.
Over the years, I’ve found that I’m most successful with plastics that remain attractive at rest. So let’s use a silt bottom as an example. If your choice of plastic is compact with short appendages, like a tube or grub, then your bait may get completely covered in the soft silt at rest, rendering it invisible to the fish. If you were to use a slightly larger bait with longer appendages, it likely won’t disappear in the silt, and the tentacles protruding from the bottom may actually entice the bass. This is one reason why baits like large worms and gangly creatures work so well in swampy regions. On the flip side, in Northern regions where rocky and hard bottoms are more common, you’re more likely to have success with the compact plastics that bounce off the rocks while remaining highly visible and keeping definitive bottom contact at all times.
This is not to suggest that local forage size, water clarity, and temperature, shouldn’t still play a role in choosing a plastic. But you should make the effort to strike a balance between those factors and bottom content. Sometimes that means carefully choosing your weight and rigging style. If, let’s say, you felt a tube was the best choice over really soft bottom, Texas rigging may help that lure protrude from the silt at rest better than if it were rigged on a jighead. Just remember if your bait is taking the subway underneath the Main Street parade, you won’t put as many fish in the boat as you could.