While inspecting the blades, the under-side of the deck should be checked and cleaned of debris. Lush damp grass, such as early spring growth, causes debris to build up rather rapidly under the deck. This is often the cause of cut quality complaints. It will also have an effect on the rate at which blade wear occurs.
The top of the deck should also be cleaned off regularly. Grass clippings and other debris will build up, especially under the belt guards. This can lead to premature belt wear and damage. It can also affect bearing life in pulleys and tensioners.
Another area to watch is around the engine shroud and cooling fins. If these get too restricted or plugged with debris it will cause the engine to run hot possibly leading to premature wear and/or engine failure. It is a good idea to blow off the engine periodically. This is especially true in the fall or other dry periods when the grass clippings and leaves are lighter and tend to build up more.
On Liquid Cooled Engines the radiator fins should be cleaned and the anti-freeze level checked and topped off if necessary.