I just thought of another small example to think of.

We all want more grip, we all want traction, with more traction we can achieve faster lap times.

Ever wondered if lower RC always achieved more traction, then why dont all manufacturers just lower the RC as much as possible? Then we can all go race with max traction.
That is because there is a LIMIT and balance to everything. If you EXCEED ideal rear RC the car will just drift into corners excessively if its too low; and it will drift or spin out effortlessly if its too high. If the front RC is too low or too high it will PUSH.