Billy Godleman suggested the Edgbaston pitch had offered "excessive turn" and bemoaned his side's failure to adapt to conditions after losing their T20 Blast semi-final against Essex.
Derbyshire lost eight wickets to spin - four to Simon Harmer, three to Aron Nijjar and one to Dan Lawrence - and struggled badly in the middle overs after flying out the blocks, and Godleman suggested that "the better team won" on the day.
"There was excessive turn," he said, "which obviously provides challenges for hitting boundaries, but our job as professionals is to adapt to whatever conditions we're given, and try to find a way to be effective.
"Unfortunately for us, Essex were a lot better at that today than we were."
Godleman said that he was "slightly concerned" at the interval after Essex had posted 160 for 5 - the highest total across the two semi-finals - and that his side had conceded an above-par total.
"I thought the way that Alex [Hughes], Matthew [Critchley], and Luis [Reece] bowled," he said, "taking pace off in the middle, I could see that it would be difficult against their spinners in the second half of the game. I thought anything over 140 would be difficult."
But Godleman reflected that his side had come a long way in the past three seasons, which have all been under the stewardship of specialist T20 coaches - first John Wright, and then this season Dominic Cork.
"We're very proud, very happy with the accomplishment of making it to Finals Day. It's obviously bittersweet - you get here, you're part of the day, it's such a great atmosphere, and you just think 'win two games and we'll lift the trophy'.
"I think once these 24-48 hours pass by, the real context of what we've done as a club, playing with only one overseas player, giving opportunities to a lot of our talented homegrown cricketers, and being able to beat a lot of the big counties home and away, make it to Finals Day - we're really proud."
Godleman suggested that his side had taken plenty from their quarter-final loss to Hampshire in 2017, and said that in the future he hoped they would reflect on this defeat as something to learn from in the future.
"Two years ago, we made a quarter-final and got beaten quite badly by Hampshire," he said. "This year, we made a quarter-final, we won it convincingly, and some of the guys who played in the defeat to Hampshire a few years ago really gained from that experience.
"Hopefully next year, or in the next 24 months, we can make another Finals Day and draw upon this experience."