City Council roadblocks have cost Detroit a much-needed hotel project, and there's no good reason that should have happened.

The council for the second time last week voted against rezoning for a proposed second tower of the Crowne Plaza (formerly known as the Hotel Pontchartrain). The owners now say they're putting the project on hold indefinitely in favor of building a hotel in Houston.

The reasons are nebulous at best. Various councilpeople have complained about the quality of the hotel's housekeeping, voiced a desire to get employees' pay to $15 an hour and referenced a failed unionization drive at the hotel dating to 2015.

None of these are reasons to reject a plan that would be a clear win for a city that needs hotel rooms in large blocks.

It's true Detroit is experiencing a hotel construction boom, but most of those projects are smaller, boutique hotels like the Foundation Hotel or the Shinola hotel that is still in the works.

Event organizers have cited a dearth of hotels that can offer large blocks of rooms, several hundred or more. The deficiency was seen as a key reason the NCAA passed up the city when awarding men's basketball Final Four bids earlier this summer.

The Crowne Plaza's owners, a Mexican investment group called Operadora de Servicio Para Hoteles de Lujo, want to build the 500-room second tower, which would seem to fill that bill nicely. The location just across Washington Boulevard from Cobo Center is a bonus.

The owners aren't asking for any taxpayer money. The project would add 250 jobs in the city.

It seems like a no-brainer. Not for the council members who have now twice rejected it. They are far exceeding their mandate by interposing themselves into management-labor relations and room cleanliness. We may be going out on a limb, but we'd bet there are plenty of lodgings in the city that are more dingy.

If this were Detroit's "bad old days," we would wonder if the hotelier failed to make campaign contributions to the right council members.

But another motive is apparent in the latest request from the council members — to secure a pledge by hotel management of a neutral stance toward another unionization effort. What unionizing has to do with zoning is beyond us.

Playing labor politics in a way that costs the city jobs and hotel rooms (which could help secure more jobs through more convention business) is just plain wrong.