TX No knife remains sharp indefinitely.
Serrated knives stay sharp the longest, but they have very limited uses.
The edge of a serrated blade is rough, which helps it grip food and slice as you move the knife back and forth. Also, it's impossible to chop well with a serrated blade. Chopping and slicing are actions based on hitting the cutting board and sliding through what's being cut. Serrated knives grip, so they can't slide, and when they finally become dull, they can't be resharpened. Knives become dull from contact with food and work surfaces and from the acids in the foods themselves, which can corrode a knife's edge.