Why does turn one suck so much?

I hate to say it, but turn 1 sucks because people suck. If you drive as hard as possible into turn 1, you will crash and you will lose places. If someone else drives as hard as possible into turn 1, you may crash and lose places. In general, turn 1 is one of the most frustrating parts of a race unless you handle it well.

How do you handle it well? Well, first and foremost, you need to internalize the concept that A RACE IS NOT WON IN THE FIRST TURN. No matter how many juicy opportunities you see to slip between cars and pick up places, you need to show some restraint and play it safe because odds are the time you'll gain on average from managing to pass two people who decide to brake to avoid a crash is going to be less than the time you lose on average from being the idiot who causes a crash. And then the people behind you, the ones who waited to see what happened? They get to pass you for free. So don't do it.

All of this applies to the next turn and the whole rest of the race too! Slowing down when you see a crash ahead or the driver ahead of you starting to lose control can be the difference between a massive pileup and clean, fun racing.