The Kangaroos worked back into the contest and cut the margin to four points in the third quarter, but they couldn't stop another Gold Coast surge led by Gary Ablett.
It was the fifth time in seven games the Roos had entered quarter-time trailing, and Scott said it was an issue that needed to be sorted out as the team goes into the bye with a 4-3 record.
"Our starts are killing us," Scott said.
"You look back and you think, last year we were the best first-quarter team in the competition.
"We've got to get to the bottom of it and work out why, because it's a pretty even game after that.
"But you concede a seven-goal start, you're chasing your tail trying to come back."
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Aside from the team's slow starts, Scott said he didn't have an answer to why the Kangaroos had been so inconsistent this season, beating preliminary finalists Fremantle and the Sydney Swans but losing badly to Collingwood and Essendon.
He said the team had been addressing its 'Jekyll and Hyde' form since returning from their round six win over the Dockers.
He said conceding late goals in the third quarter to Suns Harley Bennell and Charlie Dixon had hurt after the Roos had worked back into the game on Sunday.
"If it's a five-point game at three-quarter time it's probably a different sort of a game – they don't play seven defenders in the last quarter because they're trying to protect a lead," Scott said.
"We certainly went into the last quarter trying to attack and trying to win the game and we opened up our defence by doing that.
"But we're there to try to win the game, not to try to lose it by a small margin."
Scott praised the Suns' speed through the midfield, crisp disposal and the form of their tall forwards – Charlie Dixon, Tom Lynch and Sam Day – who were "better than ours".
"Credit where credit's due. I thought Gold Coast were fantastic," he said.
"Don't take anything away from them. In this industry we look to criticise and critique others.
"When we went into quarter-time, we were 12 down in contested possession and just getting beaten in the contest … they were effective going forward.
"We couldn't get the game on our terms."
Scott said midfielder Daniel Wells (foot) and captain Andrew Swallow, who is returning from an achilles injury through the VFL, were likely to be available after the round eight bye.
