If you remove the normal piston from the perpendicular stuck-piston based BUD, you'll see there is a bug. Watch the attached video.
MC-75848
Sticky piston wont retract blocks if it's retracted too quickly
Resolved
Duplicate
0
Lucas Ignacio Morrison Osorio
(Unassigned)
Unconfirmed
Minecraft 1.8, Minecraft 1.8.1, Minecraft 1.8.2-pre1
Retrieved
Thank you for your report.
However, your ticket has been resolved as a duplicate.
This issue has been linked to the original bugreport: MC-5726. You can find or add further information on that report.
Please search before reporting any bugs, as it's likely that one exists already.