Depends on what you have been exposed to. The Victa reel mowers and those mowers with swing blade bars look a little strange to me but I like knowing about how other countries are building mowers.
Simply, a reel mower runs a barrel with helical blades that spins toward the user, it then rubs against a blade that is fixed and effectually slices the grass like scissors rather than slashing like a knife.
They are often called a "greenkeeper" mower and are almost exclusively used on manicured type lawns. In fact they will leave tall stalks uncut as the method folds them down so the blades do not contact them.
Nothing will give the the quality of a reel on a well kept lawn but nothing is as worthless as a reel mower an long grass.
I only mow the front verge of my house with a greenkeeper as it is the only piece of grass that I keep to a standard that deserves it.

I think that i keep it that good so I have the chance to at least use my reel mowers?? Chicken or the egg...
If you're a member of a VERY expensive golf club you'll see a towed gang of "scissor" mowers doing the fairways.