CARDIFF - Warren Gatland admits Wales should have beaten Samoa far more comfortably after a narrow 17-13 victory at the Millennium Stadium on Friday.
Wales went ahead thanks to wing Leigh Halfpenny's sixth minute try, but the home side were pegged back by the South Sea Islanders after the interval.
They then survived a late onslaught after Seilala Mapasua's intercept try brought the scores to within four points.
"We wanted to be more ruthless in our approach, but unfortunately we weren't," said Wales coach Gatland. "We created a lot of chances and 11 line breaks to their two and should have put the game away comfortably.
"But our finishing simply wasn't clinical enough. We have to learn from our mistakes and in the first-half we kept kicking the ball away.
"We felt physically that if we kept playing with tempo their forwards would struggle and tire later on. It was a very frustrating game and we didn't get any real momentum going."
Wales cruised into a 17-6 lead before number ten Dan Biggar allowed London Irish centre Mapasua to blow the game wide open in the 62nd minute.
Gatland admitted his men only had themselves to blame after a close shave in a tense finale.
"The game should have been out of sight by the time they got their interception try - that was a 14 point try because if he hadn't have caught it we would probably have scored," said Gatland.
"It was a little bit too close for comfort in the end and we put ourselves under pressure. But we have come away with a win."
Wales will face Argentina at home next Saturday on a newly-laid pitch after an announcement confirmed the surface had been contaminated by Bibionidae fly infestation.
Samoa arrived in the UK aiming for a brave performance to put a brief smile back on the nation's faces following the terrible tsunami only six weeks ago.
And while they achieved that, the tiny Pacific island could have secured a famous triumph - and their third in the Welsh capital - in the final quarter as numerous chances went begging.
Now Samoa can travel to Paris next weekend ready to commence battle against one of the best northern hemisphere nations again.
"The boys can be very proud of themselves for pushing a top tier nation so close," said Samoa captain George Stowers.
"It was a case of so near but our performance showed we deserve more games against the big teams especially after just a few days together.
"For many of us it was the first time we had played Wales so this was a great heads up for where we are against the best teams.
"Against France next week we have to be smart, keep our discipline and play for the full 80 minutes as well as putting in the big hits."