Mitchell has replaced Ashworth after the latter's move to Manchester United.
"I think it's difficult coming into a predefined strategy," he said. "Should our scouting and recruitment be driven more extensively with a wider reaching net? It definitely should, because this is becoming a really nuanced space now, when you can't just capitally fund everything every year and buy loads of players at peak age and peak price. Of course it needs to be, and that's the responsibility of me, the scouting team and Eddie (Howe).
"Is it fit for purpose? Not last winter gone, the winter before that. Is it fit for purpose in the modern game? Because other clubs that have adopted a different approach over time, with more intelligence, more data-informed than we are, actually prospered in this window. That's where we have to grow to be now.
"You look at the money we have invested up to this point, £250 million net over the last two-and-a-half years. Was our model in place to be able to spend more to the levels we would have liked to enhance the team? I don't think it was, because we haven't sold a player during that time, barring what we were forced to do through PSR.
"We didn't have the sales window we thought we would have – and we have to look at that strategy as well, was that right? It was all aligned with the head coach. There definitely has to be a more strategic approach that we haven't had the last two-and-a-half years. I'll know whether we've done a good job in five years' time."