To unionize or not to unionize—that’s the question facing the nurses of Mission Hospital. Here are three things they should consider before casting their votes:

1. Your vote may be forever. Unions don’t have to stand for reelection, so a yes vote today may last a lifetime. Only 6% of private-sector union members today have ever actually voted in favor of the union that represents them.

So, what can you do if it turns out the union isn’t representing you the way you want? Not much. While it’s possible to decertify a union, it’s extremely difficult to do so. Workers must get the signatures of 30% of the bargaining unit within a 30-day window that comes up only once every three years, and they can’t collect signatures while employees are on the clock or in work areas. In other words, fat chance.

2. Workplace flexibility and advancement opportunities are limited. Formal benefits like paid time off, flexible schedules and good health insurance are incredibly helpful. But so are flexible working arrangements—especially for working moms with young children.

As the “middleman” between workers and management, union leaders get to pick which workers’ voices get heard and which are muffled. Inhibiting one-on-one communication can make it difficult, if not impossible, to arrange schedule changes or time off to meet urgent, personal needs.

Union contracts also often decouple performance and reward. Seniority-based pay and benefit structures eliminate performance-based promotions and bonuses.

3. Patients’ lives and well-being could be at risk. The NNU regularly calls strikes. Striking nurses lose their regular pay, and the NNU does not appear to have a strike fund to cover lost wages. It does, however, fine nurses who opt to cross the picket line.

Aside from these financial concerns, nurses also worry about what will happen to their patients if they don’t or can’t work. And rightly so. Research shows that the rate of hospital mortality rates is nearly 20% higher among patients admitted during a strike than among patients admitted in nearby nonstriking hospitals at the same time.

The nurses voting at Mission Hospital should know there is likely no going back if NNU wins this election. If the union makes changes they don’t like, denies them flexibility and opportunities, or calls strikes, they will have little recourse. That’s not good for them or their patients.