On a stainless steel pan, ground meat cooks rapidly and browns faster. On a non-stick pan, the browning is slow and the cooking is long and hard. This leads to dramatically different texture and taste (lamb for instance tastes ‘sweeter’ and has a softer texture) between the two methods. Stainless steel cooked meat tastes so much better, with the meat’s flavour coming through.
This might be because stainless steel pans distributes and holds heat better over time.