Diminishing returns.
Just like tuning an engine. In the beginning easy, quick and inexpensive modifications produce big results. The further you go the more complex, time consuming and expensive the modifications come while the visible gain gets smaller and smaller.
I couldn't care less for graphical stuff but as atledreier wrote: more damage. It would make races more interesting. Apart from the random electrical failures. That's a big no no.
Abuse your car => damage = Good!
Random damage = Bad!
Just like tuning an engine. In the beginning easy, quick and inexpensive modifications produce big results. The further you go the more complex, time consuming and expensive the modifications come while the visible gain gets smaller and smaller.
I couldn't care less for graphical stuff but as atledreier wrote: more damage. It would make races more interesting. Apart from the random electrical failures. That's a big no no.
Abuse your car => damage = Good!
Random damage = Bad!