Vettel has only two race weekends left before he hangs up his helmet, with this weekend's Sao Paulo GP followed by Abu Dhabi a week later.
The German insists that the only person he has to satisfy in terms of his performances is himself.
"The way I think about this," he said when asked by Motorsport.com about going out on a high.
"And I thought about a lot of things before making the decision, and there's a lot of thought from the outside maybe for people, is it important to have a good race?
"Of course it would be nice to win my last race, being realistic, I think it's going to be very difficult!
"And of course from the outside, you think it will be much better to go out on a high, and so important to win the last race, or to win another championship, or win the championship and then retire.
"But the way I felt, the more I thought about it, is that the only person that it really matters to is myself. So of course, you could say that it's a nice story, and it's a nicer way to go. But then who's got to cope with the leaving anyways?
"No disrespect, not you or the general opinion. It's only me in a way, not being egoistic. But that's the way I see it.
"So I'm at peace with it. I know that my last race probably will not be the highlight of all the whatever how many races I've done. It doesn't matter too much."
After an often frustrating second season with Aston Martin Vettel put in charging performances in the recent races at Suzuka and Austin, winning a last-lap battle on both occasions and showing signs of his old fire.
"I mean, it was great, obviously," he said. "I enjoyed these races a lot more than I did, for example, Mexico, where you are just going backwards because you're too slow. So that's for sure.
"But I think overall, I am so lucky that I had so many races where I was going forwards, and not just going backwards."
Asked to sum up his career Vettel said it was too early to make an assessment.
"I haven't looked back yet. So maybe that's more for the question for 10 years' time. But yeah, I'm very happy with it. Obviously, I had a lot of highlights, a lot of great races, great people that I got to know and work with.
"Surely there are some moments that maybe weren't great, but I think they helped me to arrive where I am today.
"So I don't have any real regrets. I think I had a very good time. That sums it up. I think it's been a privilege.
"And I'm very happy to take all of this, everything that I learned, everything that I was able to experience, all the support that I got, as well to hopefully boost me in the next chapter."
Asked if he was feeling nostalgic he added: "I don't know how it will be next week. But yeah, I don't know if I look very nostalgic at the minute!
"I look forward to the race here. I think sometimes I spend too much time thinking of what's next, and not enjoying so much the present.
"But I hardly spend time looking back, other than understanding why was I so slow, what were we missing? And so on."
