What's the Catch?

The vast majority of used cars are sold by car dealers. Of those who buy, a high proportion do so from the first dealer they visit. There are several reasons why this should be so. Firstly, car salesmen are generally experts at what they do and rely for a living on their ability to negotiate with ease. They offer the car buyer a service, and much of that service is to remove the necessity to make painful decisions.

The mystical complexities...
To most people, the motor car is a complete mystery. They may be completely dependent on their car, but as long as it starts, stops and goes in between, they're happy to just turn the key and work the controls. That's as far as they want to get involved. When it comes to buying and selling a car, they want to be involved as little as possible. They look to the dealer as the 'expert', in tune with the mystical complexities of the workings of the car and are happy to leave much of the decision making to them.
People pay a hefty price... Car dealers rely on the public's aversion to making decisions. By and large they're not in the business of lumbering people with piles of unreliable junk. The majority of car dealers provide a genuine service to the public by helping them to provide the type and price of car to suit their needs. They take away decisions which most do not wish to make. For this service, people pay a hefty price.
'THE CATCH' with car auctions is not that all the cars there are worn-out rubbish, it's not that they're unpleasant places to attend nor is it that buying at auction is a difficult process. 'The Catch' is that any decisions which have to be made are entirely up to YOU.

YOU have to decide...
We are assuming that a potential car buyer has done at least some research, and has some preferences for whatever reasons for a particular make or type of car. When you go to an auction, rather than a car dealer, having done your research, it is YOU who has to evaluate the condition of a car; not always under the most ideal circumstances. YOU have to decide how much to bid, and YOU have to resist the temptation to exceed that amount. If you want to make a success of operating in an environment which is still very much that of the 'expert', then you must take responsibility for your own actions.
Auctions are not the easy path to used car purchase. Even to someone with years of auction experience, bidding can still be a daunting experience. There are plenty of things, which you can do to minimize any risks you might be taking, which I will go into later; but the final blame or glory will rest on YOUR shoulders.