I can't figure it out. A cold startup or restart, and my iMac boots into Recovery Mode. I have to hold down the Option key to select the El Capitan HD. I've selected it as the startup disk, used Disk First Aid, but nothing is helping. I don't reboot that often, but it is still an annoyance.
I don't want to re-install from Time Machine, and I've never had to install from recovery mode. I'm baffled.