The first patents for automatic flush toilets surfaced in the 1970s and 1980s. Clients were wowed by their hygienic offerings and the fact that toilets would actually flush each time they’re used, avoiding that maintenance headache of a mess that’s been left in a toilet for hours. Industry-wide, sales for automatic flush fixtures have doubled in the past decade, said Orkun Onur, commercial product manager at Kohler, the large plumbing-fixtures company. Onur credited this to automatic toilets’ decreasing price and improved technology, but he did not provide any precise data.

Despite that massive boost in sales, these toilets have often irritated, angered and perplexed those taking care of their bathroom business. Users typically find it irritating when these toilets flush with the opening or closing of a stall door or with a person’s slightest movements, sometimes splashing water. On the other end, some automatic flush toilets refuse to flush unless you actually press a manual button.

But these anecdotal complaints overlook an even bigger problem with the technology. It’s a tremendous waste of water at a time when water is increasingly limited.