Flexible work arrangements sound good in theory. Let employees work when it’s most efficient for them. They’re adults after all. Early risers roll into the office at 7AM, parents can leave at 3PM to coach their daughter’s softball game. If they want to exercise for an hour at lunch, let them.

There are countless benefits to flexible work arrangements. They make employees happy. They show that companies care about an employee’s life outside the office. Most importantly, they help attract talent in an extremely tight job market. In fact, a Zenefits report found that 77% of small business employees said flexible work is a major consideration when contemplating a new role. Meanwhile, Dell reports that 60% of its employees work before or after standard working hours and GlobalWorkplaceAnalytics.com reports that 80 percentof American workers say they’d like to work remotely at least part-time.

The wave of support has gotten an increasing amount of employers to embrace flexible work arrangements but far too often, they screw it up. Managers sabotage flexible work arrangements by rewarding presenteeism, expecting employees to check email around the clock, and failing to weave flexibility into corporate culture.

“The next generation of leaders want to be able to work where they want and when they want,” said Avery Blank, a leadership expert and business consultant. “Flexibility allows people to work better, not less. You need flexibility to attract talent and maximize productivity.”

Here are five ways managers ruin flexible work policies—and some easy ways to fix them.

Managers don’t personally work flexible schedules.

If the top bosses don’t work flexible hours themselves or frown upon employees who arrive after the ungodly 10AM hour, then your flexible work policy will die a quick death. Flexibility needs to be woven into your corporate culture so employees actually feel comfortable taking advantage of it.

“Great managers model behavior,” said Blank. “Reports will be more likely to practice (and feel comfortable practicing) flexible work if they see you doing it as well.”

Managers reward facetime

Some managers have an old school mentality, and will only believe that employees are working hard if they see it with their own eyes. Such managers may relegate remote workers to second-class status, hurting their chances for promotions or increased responsibility. Instead hire managers that truly embrace flexibility and reward people for doing great work, not for being present.

“Some people are not as productive in a formal office setting or during traditional work hours,” said Blank. “Great managers give their employees autonomy and trust them to know where and when they work best.”

Managers don’t set boundaries

Flexible work can be easily abused. Plus, you can’t really hold meetings or schedule important events if teams are never online at the same time. Employees need clear instructions from the top so they know what’s okay and what isn’t.

“People will push the boundaries of any flexible plan if they aren’t given a clear picture of what those boundaries are,” said Kris Hughes, senior content marketing manager at Austin-based software company, ProjectManager.com who has led large teams at several companies. “There’s nothing more important for a manager who wants to install a flexible policy to make it crystal clear what’s acceptable and unacceptable within the policy, and sticking to their guns when these boundaries are crossed.”

Managers rush into it

Maybe your culture just isn’t ready for flexible work. Maybe staff and management just need to be eased into the process. Start with a special flex day—Flexible Fridays has a nice ring to it—and work up the frequency from there. Just because it seems like a great idea doesn’t mean it’ll work for every company.

Managers expect workers to check email any time

Flexible work arrangements can backfire if employees are expected to be on call 24/7. A Virginia Tech study found that the expectation of checking email from home resulted in increased anxiety and negatively impacted relationships due to the competing demands of work and non-work lives. In fact, employees don’t have to actually check email from home to be stressed out—the mere expectation of it leads to anxiety.

Allow your workers to actually be off the clock. Follow the lead of Philadelphia-based Vynamic which instituted “zzzMail”—forbidding email on weekends and between 10 p.m. and 6 a.m. during the week.
“As a father of two, I’m personally thankful for all the moments I’m fully present to enjoy the crazy bliss of family instead of checking email,” CEO Dan Calsita wrote in Philadelphia magazine. “I don’t think I would have had the willpower to self-assert this policy if it weren’t something everyone in the company is challenged to stick to. Knowing that we’re not expected to reply to email gives each of us a true break.”