I tried a couple of PC racing games once. F1 2010 and the other one I don't recall the name.
While the graphics were great, and the physics were decent... what killed all enjoyment of them for me was the horrible AI computer opponents. Funny enough the AI cars never seemed to run into each other, but always drove into me. They always seem to follow a set racing line whether the player car is there or not.
In F1 2010 I remember I tried running a full length race simulation at Spa once. (including qualy) I qualified and started mid pack but after about 10 laps I settled into a groove and began to gain on those in front. After several laps of closing down the next car up the road I got close enough to get a tow down the long straight, pulled alongside on the inside line into Les Combes, had my front wheels well in front of his, hit my braking perfectly... and he turns in and crashes me.

I limp back to the pits for repairs and a new set of tires and get back out. Now of course I'm the back of the field but much faster than those immediately in front of me, I quickly catch one and try to pass on the inside at the chicane... and he blindly turns into my rear end and crashes me again.

As an F1 fan, I tried to get into that game for several weeks, but every time I'd start to get into it, some silly AI car would stupidly crash into me... it's like every AI car was Romain Grosjean 2012. It was the same story with the other racing game I tried, I think it was Need for Speed, but I can't recall for sure.