5 Reasons Not to Install OS X El Capitan and 7 Reasons You Should

Install OS X 10.11.5 or higher if Your MacBook Freezes

Over the last two months reports of a freezing problem with OS X 10.11.4 on newer MacBook Pro models including the 13-inch MacBook Pro Retina from 2015 surfaced. This can leave the new MacBook locked up and unresponsive at random times.

When this happens you will need to hold the power button to reset the MacBook. If this happens you will lose what you are currently working on. There is a growing thread of complaints from users who are stuck with this issue. 

At this stage it only appears to impact newer MacBook Pro Retina models, and only with the OS X 10.11.4 update. If you are already on this update you need to install the OS X 10.11.5 udpate. Apple did not list it in the changelog, but users report that this fixes the Macbook Pro freezing problem on OS X El Capitan.

If you are still on OS X 10.11.4 and your MacBook freezes, you should upgrade.