Guernsey Raiders head coach Jordan Reynolds says the club does not have the depth of squad to gain promotion to National Two South.
Guernsey are mid-table in National Three London, while rivals Jersey have just published a five-year plan to target the Championship play-offs.
"At the moment I think the club is happy where it's at," said Reynolds.
"Squad-wise there's absolutely no way we'd be able to compete in National Two," he told BBC Radio Guernsey.
"We have maybe 20 guys that could definitely compete, but I think you'd need a squad of around 45 to compete at that level because the recovery times that go into that are just so tough," said Reynolds, who became Guernsey's first full-time coach in October 2014.
"From a skill base I think we're kind of there, but we just need the personnel.
"As much as we'd like to get promoted and do everything like that, I think long term, unless we fix things that are outside of what we're doing on the pitch, it's going to be pretty difficult for us."