The lockout and rebound systems work by using pressurized oil to change the speed of compression and decompression. A completely disengaged lockout will allow the oil to flow quickly through the chamber while a fully-locked suspension will completely restrict the flow of the oil.
Are lockout forks worth it?
Registered. You definitely don’t need a lock-out on your fork. On steep smooth climbs where you’re out of the saddle a lock-out is nice – as it prevents the front end from bouncing up and down. However it’s not necessary, and unless you spend a lot of time out of the saddle it isn’t important at all.
When should I lock my front fork?
Usually the only times you would lock out your rear shock (or front fork) would be when on a long non-technical climb, or other long distance ride. Mountain bike suspension often features multiple modes, to better set up the bike to climb or descend, and one of these common features is the lock out.