MIAMI – In the back rooms of hotels around the nation, managers and their workers juggle a tricky balancing act — one that the industry is sometimes loath to discuss.

On the one side are the economics of a seasonal, consumer-driven business and the intricacies of overseeing large, diverse groups of people, said Kevin Murphy, chair of the hospitality services department at the University of Central Florida in Orlando.

U.S. hotels, which earned an average profit margin of about 38 percent in 2016, according to hotel data and analytics firm STR, are prey to the vagaries of the traveling public.

Last year in Miami-Dade County, hotel performance slipped to levels unseen since the Great Recession because of the local transmission of mosquito-borne illness Zika, a severe dropoff of travel from Brazil and a ballooning number of new hotel rooms.

But on the other side are low-wage hotel workers, many of whom live paycheck-to-paycheck and are directly affected when the number of visitors slide. During the height of the Zika epidemic in 2016, for instance, some Fontainebleau hotel housekeepers in Miami Beach reported getting little work. Gerdine Verssagne, a 36-year-old Fontainebleau housekeeper, said that from August to January, there were weeks where she only worked one, two or three days. Sometimes, she was not scheduled to work at all.

Though statistics are difficult to pin down, housekeepers could account for as much as one-third of Miami-Dade's hotel employees. While making enough money to keep their families afloat is their primary concern, their worries extend beyond wages. Erratic schedules, workload, hostile conditions and benefits — which can vary widely — contribute to the complexities of their employment.

In Miami Beach, a housekeeper in a non-union hotel can expect to start at minimum wage, $8.10, or slightly more. Workers at the unionized Fontainebleau for instance, start at $11.45, said Wendi Walsh, secretary-treasurer of Unite Here Local 355, the county's only hotel union. The Fontainebleau's housekeepers have better conditions than most. Their union contract limits the workload to 14 rooms per eight-hour workday, with half an hour for lunch. Each worker also gets health benefits and paid vacation-and-sick time. The Fontainebleau and the Miami Beach Resort are the only two Beach hotels with union representation.

At other hotels, lower wages are likely. Benefits including health insurance and paid time off vary widely. Some workers at other hotels have reported cleaning nearly 30 rooms a day and not receiving raises for three decades, Walsh said. Workers at non-union hotels refrain from discussing conditions openly.

Walsh and her members say that at many hotels, managers cultivate fear. "A lot (of the housekeepers) end up staying nine, 10, 11 hours to finish up a room." Even at the Fontainebleau, some housekeepers say they are afraid they'll be replaced if they don't finish on time, and routinely skip lunch or stay later to finish cleaning rooms.

Many of them have never seen the lobby.

Complaints about work conditions are common nationwide in the hospitality industry. Some are simply a function of the demand-driven business, say experts.