Former New Zealand men's sevens coach Gordon Tietjens believes one lapse in judgement can prove costly for his Samoan side at Rugby World Cup Sevens tournament in San Francisco.
Tietjens said his Samoa sevens team need to be perfect in their execution to reach the finals.
"There are no second chances in this format, you lose one and you are out," said Tietjens.
"You can't afford to start slowly, it's really important that we get off to a really good start".
Tietjens says the Pacific nation has struggled a lot on the world circuit since their 2009 World Series win.
"Probably two things really, the lack of resource you know they haven't got the facilities like in New Zealand and we haven't got the depth either," said Tietjens.
"And we are trying to build depth particularly on the island, to get them to play the pace of the game that needs to be played in on the World Series."
Samoa finished 10th on the World Series tournament this year.
"The physicality has always been there with Samoa that’s one of the real strength of theirs but it is the pace of the game and building depth – those are the areas that we need to get better at."
Tietjens coached the New Zealand men’s sevens side from 1994-2016.
Every game of the men's and women's Rugby World Cup Sevens will be live from July 21-23 on TVNZ's Duke channel - Freeview 13, Sky 23, and streaming on tvnz.co.nz.