Wales coach Warren Gatland lamented the goal-kicking failures that hampered his side's World Cup campaign.
Gatland said: "The kicking's been an area of strength in the past.
"But for whatever reason we've missed some in critical moments here and it's cost us."
Hook was replaced by veteran Stephen Jones in the 50th minute against Australia and the Scarlet kicked a conversion and penalty.
However, Wales will look back on other failures in this tournament when the posts were in sight.
Against France, Hook missed two penalties and a drop-goal attempt, while veteran Jones missed a potential match-winning conversion and a drop-goal attempt.
In the closing stages of their opening 17-16 Pool D defeat by South Africa, Rhys Priestland missed a drop-goal attempt and Hook missed a penalty, either of which could have brought victory.
Gatland added: "At this level you have to take your opportunities.
"Unfortunately on these big occasions our goal kicking has let us down.
"If we look at the past, those kickers who have been taking goals have been in the 80s [%]. James missed one almost in front of the posts.
"It's pretty important in the scheme of things and it's probably what cost us."
Gatland also conceded Wales were not as 'emotionally' ready for the play-off as they had been earlier in the competition.
He said: "Probably the learning that we took from tonight is that we weren't quite as emotionally up for it as we have been for other games. I think that showed.
"Our performance was probably a little bit down on what we're capable of.
"In saying that, we've played one of the top sides in the world and posted a very close score and scored two tries against them.
"They've been one of the best defensive teams in this competition and only conceded four tries in their pool, they didn't concede a try against South Africa, and the All Blacks only scored one try against them.
"So we're disappointed, but we've got to take a lot of positives from this tournament and how well we've done and the way we've progressed as a team."
Replacement fly-half Jones said: "We've lost three games so closely. One of the easiest things to look at then is goal-kicking.
"I would be interested to look at our statistics compared to other teams.
"We thoroughly enjoy working with [kicking coach] Neil Jenkins. He challenges us and he wants us to be the best out there.
"We set ourselves high standards, and it is frustrating when it doesn't go our way.
"We do put a lot of hours and effort into our kicking game, and it's important that we do because it decides matches."
Wales' stand-in captain Gethin Jenkins said he was proud of their achievements in finishing fourth at the tournament, despite the disappointment of finishing with successive defeats.
Jenkins said: "We're all pretty down in the dressing rooms. We know we're better than that and know we could have put a better performance in.
"But we're also a bit realistic - Australia are a very good team and a dangerous team.
"I'm proud of the way we finished. We've just come up short again today, but we've enjoyed the tournament. It's a shame we couldn't finish it off with the win."
The defeat means Wales' third-place finish at the inaugural 1987 event remains their best World Cup performance.