Vettel was the only driver to brave the switch to dry tyres in a damp race at Istanbul Park.
The four-time champion was running in 10th ahead of Esteban Ocon when he decided to pit for mediums with just over 20 laps remaining.
Vettel spun almost immediately out of the pit lane before tip-toeing around back for a new set of inters.
The Aston Martin driver went on to finish a lowly 18th, only beating the two Haas drivers.
Reflecting on the call to fit slicks, Vettel said: “I couldn’t make them work, it was the wrong call. I wanted to try because there wasn’t much rubber left on the inters so I thought that the dries would be any different or a little bit better as the grip is higher. It couldn’t break the tyre in and I couldn’t get any grip so we lost the race.”
Vettel admitted that it was “tempting to try” the dry tyres having struggled for pace before stopping.
“I am obviously disappointed having made the wrong call. On the other hand, it was tempting to try but it was the wrong decision. We lost the run for points, maybe one or two but in the end, we didn’t get any.”
Teammate Lance Stroll enjoyed a solid race to finish ninth in Turkey.
Assessing his weekend, he said: “Yeah I think it was a good effort. Conditions were very tricky and we did a very good job. We didn’t have the fastest pit stop so maybe we could have challenged Sainz but I think he was a bit quicker than us today. Looking back at it, we got pretty much everything out of it.”