I am sure this is a big part of the issue when people ignore the light -- they know one or more of the sensors is dead and it is possible one of the remaining good sensors is warning of a real situation but they'd never know it because the light is always on. I was a bit surprised to learn that many people put a small piece of electrical tape over the dash light 100% ignoring the warning, whether it's a real situation or not. Personally, I like everything to work and it's worth $200 every 12 years to replace the sensors. Most people don't keep their cars this long.Or, they may not replace sensors as the batteries die.