In a commentary in the Journal of the American Medical Association, Mitesh Patel, David Asch, and Kevin Volpp discuss the validity of claims that wearable devices promote long-term healthy behaviors. The authors contend that, although they may be useful in facilitating behavioral change in individuals already motivated to do so, using wearable devices to motivate people to instigate healthy changes is a challenge. Relatively high prices, potential inaccuracy of metrics, inconsistency of use, and difficulties in sustaining motivation are all significant barriers to success. Getting patients with chronic conditions – those for whom wearable devices have the most potential utility – to use the device regularly and to maintain behavioral changes in the long term will be challenging. The authors conclude that successful use of wearable health devices will depend more on the design of engagement strategies than the technology itself.