Approximate time to read: <1 minute
If you’re suddenly finding that your MacBook (or iMac) is taking an age to reboot then check your card reader – anything in there? Maybe a Nifty Drive or SmartSuit (even if no Micro SD card is in it)?
Whip it out and try and reboot again – it should now be back to normal speed.
No idea why this occurs but lots of people (including myself) have come across it.