Collider bias: food and location among surviving restaurants

A food critic notices that among restaurants that have stayed in business for years, food quality and location quality are negatively correlated: the best food is often in inconvenient spots, and the prime locations often serve mediocre food. When restaurants first open, the two are unrelated. He concludes that great chefs deliberately avoid good locations.

Explain why survival induces this negative correlation, and why his conclusion does not follow.