The American-owned outfit has been chasing a cure for the high tyre degradation woes that have derailed its prospects at several races this year.
Its VF-23 car appears to be quite aggressive on its rubber, which is great for switching tyres on for single qualifying laps but is a big handicap to its drivers when it comes to management in the races.
Work is ongoing at its Banbury factory to try to get to the bottom of what is triggering its problems, but Steiner is doubtful that there will be a single magic bullet that can transform its potential.
Asked how much of the problems the team understood, Steiner said: “I think some of it we understand completely. But honestly, we only understand some of it. We are running too high temperature, but there could be something else.”
Steiner said that solving problems in F1 was always a long process, and there was hardly even an occasion where a team made one simple change and its situation improved dramatically.
“You need to always fix things, but then you find the next problem. You never can wait until you have the Holy Grail.
“If I would know why the Red Bull is so fast, then why we don't do the same? So, you need to get slowly there, and everybody gets slowly there.
“You fix it bit by bit, hoping that the other ones don't make another leap so you catch up. We know our tyres run too hot, but is there something else as to why we have got such a big degradation of tyres?”
Steiner said one of the key hurdles that the team had to overcome was accepting that there was something awry with its car design that was triggering the tyre problems.
“If you see that, obviously, other people can manage the tyres differently, at some stage you need to admit it [the car] is wrong, because we get the same tyres and we've got the same wheels now as well,” he said.
“In the old days, you had different rims as well. But now everybody's got the same wheels and the same tyres, so it must be something wrong with the car. And obviously, admission is the first step to getting better.”
Additional reporting by Filip Cleeren
