1. Doctor goes somewhere random
2. Doctor starts to enjoy random place
3. Doctor discovers problem in random place which places his own and his companions' life at risk
4. Doctor fixes problem
Now, if I went somewhere random on holiday this summer, I think I would not have a high chance of becoming involved in an alien invasion, or events leading to a coup, or somesuch. Unless I had extraordinarily bad luck. Admittedly my potential vacations do not extend to all of time and space.
The Doctor doesn't have bad luck. Why does this happen then? I have a theory.
When the Doctor originally stole the TARDIS, he triggered the anti-theft device, which makes the TARDIS land in dangerous places to try to kill the thief. This, working in conjunction with the randomizer, means that he doesn't just go to random places, but to places where he is in severe danger of dying. The business where it translates languages for him is just a ruse to get him to leave the TARDIS. And you know, it's working. At least five regenerations caused by landing on random dangerous planets. Of course that took several hundred years. The man is that good. He may have figured it out and probably leaves it on for the thrill.