The England all rounder said that they either hammered teams or were hammered themselves, with their failure to win close games an Achilles heel.
Yorkshire lost five of their 14 matches, three of them by fine margins and also tied at home to Birmingham Bears. Had they won those fixtures they would have had an extra seven points and comfortably reached the knockout stages.
As it was, Yorkshire failed to get to the quarter-finals for a sixth time in seven seasons.
“Getting across the line in tight games – that’s where we’ve got to get better,” said Willey.
“If we’d done that this year, then we might well have qualified. Unfortunately, that’s typical of the way we’ve played in the last few years.
“We either blow teams out of the water or lose; it’s very disappointing.”
Yorkshire finished fifth in the North Group with four wins, two of them in their last two matches against Northamptonshire and Birmingham Bears.
It served to put something of a gloss on events, with Yorkshire only two points away from finishing bottom.
In the final analysis, they did not have sufficient match-winning performances from key performers – Willey included.
“I’ve been poor with the bat this year,” said Willey, who scored 136 runs in nine innings at 15.11 and took nine wickets at 30.33, four of them in one game against his former club Northamptonshire.
“I’ve probably not bowled as well as I’d have liked either.
“Ultimately, it’s disappointing that we’re out of the competi tion.
“We’ve not played very well throughout, unfortunately.”
Willey’s comments were echoed by Tom Kohler-Cadmore, who finished Yorkshire’s leading run-scorer in the competition with 435 at 62.14.
“I think we’ve got a lot to rev iew and a lot to make right,” he said.
“We had a nice confident end to the season, but I still feel we need to review this season properly and not shy away from how we played at the start of the sea son; we weren’t really good enough.
“Next season we have to make sure this doesn’t happen where we start slowly or we’re not executing our skills.
“We want to be hitting the season running.
“It’s important to be hard on ourselves now and ask how we can become a better team.”