When you either can think of any more examples or the list is too long you say "etc." at the end of the sentence. Other wise meaning "so on and so forth..." It stands for 'Et Cetera'.
"The new car had power locks, power windows, heated seats, etc."
1. When you do not feel like elaborating on anything. Especially when the aforementioned phrases do not link in any way whatsoever. You would end the thought with "etc." because well, you just realized...you're an idiot.
2. When you do not wish to elaborate further on a topic where it is understood what happened next.
1. I had a can of peaches and I leaned into the dryer and realized that it smelled familiar and so I...etc