Ben Stokes conceded England had not been ruthless enough with the bat after falling to a four-wicket defeat in the first Test against the West Indies.
Jermaine Blackwood scored a match-winning 95 as Test cricket's big return ended with the tourists chasing down 200 to defeat the hosts in their Ageas Bowl 'bubble'.
England set their target by squeezing 29 from the last two wickets to finish 313 all out, but it proved not to be enough.
"You've got to believe that's enough," Stokes told Sky Sports. "If you start to think that you don't have quite enough on the board then you're already losing.
"Ideally we would have liked to have got a lot more runs in the first innings.
"We got ourselves into some great positions at times with the bat and unfortunately we just weren't ruthless enough to really go on and make our batting innings count."
Stokes stood by his decision for England to bat first.
"We've got to be good enough to put first-innings runs on the board," he said.
"We got ourselves in positions in that first innings to really kick on, get 350, 400, and same when we came to bat again. We just didn't quite manage to grasp the game like we would have (liked to have) done, but it's been a massive, massive learning curve for a lot of our batting line-up and a great learning curve for the young guys as well."
He also insisted he did not regret leaving out Stuart Broad, who had played the previous 51 home Tests and admitted to feeling "frustrated, angry and gutted" at being omitted.
"If I was to regret that, I don't think that sends the right message to the other guys I picked," Stokes said.
"I think we're in a very fortunate position in that we're able to leave somebody out of Stuart's quality, and I thought the interview he gave the other day was actually fantastic – the passion he showed in that interview. I'd actually be very worried if he didn't show that desire and passion towards not being selected.
"Someone who has played that many Test matches, got that many wickets, to still see that desire and emotion is fantastic. He is nowhere near done and if he plays in that second Test match I really hope he walks off that field with a bit of an 'up you'."
Stokes said of standing in for Joe Root as captain: "I've absolutely loved it.
"I think (Saturday night) was actually my first stressful night really – the other four nights it has been all right.
"I've really enjoyed it, but obviously this is Joe's team, he's the captain and I'm really looking forward to welcoming him back into the team."
West Indies skipper Jason Holder was delighted with the performance of his side.
"It is right up there as one of the best victories we have had as a group," he said.
"To me, yesterday was probably the best day I have had in Test cricket. It was a hard, long toil and the bowlers really put in – every time I asked a bowler to come up and give a spell they came up trumps and gave a massive effort.
"Credit must be given to everyone yesterday, I think yesterday was a hard-fought day of Test cricket, and we really reaped the rewards at the very end."