"It should be obvious that we lack some skills," Dyson told reporters.
"Compared to the other side, we lack some batting skills, some bowling skills and some fielding skills.
"Australia are very good in every department plus they have a very strong squad. They've got great depth.
"We're still working on a few skills that we need to develop and we are working on the strength of our squad. It's a tall order to expect a team ranked No. 8 to beat the team ranked No. 1."
West Indies entered the match needing to win to keep the five-match series alive, but they were dismissed for 223 in 48 overs, after they appeared to be making steading progress at 160 for two in the 33rd over.
Shane Watson then made his maiden ODI hundred to power Australia to a comfortable seven-wicket victory with 57 balls to spare, after they were set 224 to win from their allocation of 50 overs.
"It's a disappointing result," Dyson said. "It's been a disappointing ODI series.
"The Test series was quite exciting and competitive. This series has been disappointing. We didn't bat well enough. We didn't bowl well enough. We didn't field well enough."
Australia won the opening match of the series by 84 runs last Tuesday at the Arnos Vale Sports Complex, and the rain-affected second ODI last Friday by 63 runs under the Duckworth-Lewis Method here.
Dyson acknowledged it will be hard to get things right for the last two ODIs which will be contested on Friday and Sunday at Warner Park in the St. Kitts capital of Basseterre.
"You need a bit of time to correct these things and they are not the sort of things that you can change overnight," he said.
"There's no denying that the guys are good cricketers. They are skilled cricketers, but they are some extra skills that would allow them to compete with the No.1 side in the world that you need.
"Throughout the Test series, I think we showed we can be aggressive, and in the Twenty20 we showed we can be aggressive, but in this particular ODI series we have been outplayed.
"We are constantly working on things, but whether you can take what you have been working on in the nets and transfer it to the middle in an ODI is not always possible. We talk about things, and we map out the way we can do things, but in the heat of the moment in the middle, it just goes haywire."