The Italian team has been blasted in the press in their homeland after they went into the season aiming to fight for the championship, only to slip behind Red Bull Racing to third in the standings.
However, considering Mercedes' dominant nature, Vettel thinks that to criticise Ferrari for not winning is wrong.
"If you look at the gap to Mercedes, it has been fairly stable," he said. "Some races we are a bit closer, some races we are a bit further away. It is fair to say that in qualifying the gap is big and in the races it shrinks a bit, but it's still there."
"At the start of the year we were clearly the second-best team, but now towards the end of the year, here and there in terms of pace, we slip behind. I think it's very close," he added. "But it's not that fair to say we are massively behind – a tenth and a half [of a second] is not big."
He did concede that losing ground to Red Bull was a disappointment that needed to be addressed.
"Fair enough, we are obviously level with Red Bull and it will be our target to get second in the constructors' [championship] back," he said. "We came into this year with high expectations, but we had to learn that we are not achieving what we set out to achieve."
"Arguably we had a lot of races that didn't go according to plan, but I think as a team we never lost focus," he added. "So even if there were a lot of things that people called bad luck, or whatever, I think we stuck to our way and that was the right thing to do. We are still heading in the right direction.
"Sometimes you wish results would come and confirm this – sometimes they do, sometimes they don't, but the most important thing is that they do, and I believe they will."
Bahrain International Circuit - Winter testing