The Saints were competitive in most statistical areas against Gold Coast on Saturday night, but were left to rue a host of horrendous turnovers close to goal.
They had 49 clangers for the match, and many of them costly.
"(Gold Coast scored) 15 goals from our turnovers, nine of them from our back end, so it's very hard to defend when you give it back that close to goal," Richardson bemoaned following the 53-point loss.
"I reckon we handballed four to them. We just gave the ball back to them way too often. That was the story of the night, we just couldn't look after the footy."
James Gwilt's third-quarter howler was indicative of their woes. The defender kicked in following a behind, directly to Jesse Lonergan, who went back and slotted the set-shot goal.
Richardson said while he was disappointed with the result following the rousing upset of Fremantle two weeks ago, he could not be critical of his team's effort.
"Fremantle was one of those performances where it has the potential to raise the bar," he said.
"Having said that, I don't question our effort. It wasn't where it was against Fremantle, but it wasn't effort … it was our inability to execute."
And the execution is something Richardson said St Kilda would continue to work at over the final month and into the next pre-season.
"The solution will be to continue to work on their game," he said.
"It was often our younger guys. We know where they're at. We've got a fair bit of work to do.
"There's no test you can do in training that simulates game day and game day is the test and we failed dismally tonight. We'll learn from that."
Twitter: @AFL_mikewhiting