So how can you tell when a tire is worth the cost? Is the most expensive tire the best tire because it is the highest price? Not necessarily, no. But at the same time you'll never find the best tire in an economy-priced model. The first thing I always try to do when a customer asks what I would recommend that won't break the bank, is to qualify the situation. What kind of car are you driving? What type of driver are you: passive, aggressive or somewhere in between? Where do you live and what kind of conditions do you drive your car in? All of these things are factored in when considering the type of tire I would recommend to suit your needs.
If a person tends to be an aggressive driver but lives in a winter weather area, then my recommendation would tend to lean towards Performance All-Season tires such as the Bridgestone Potenza G019 Grid, Michelin Pilot Exalto A/S, or the Yokohama AVID ENVigor.
Bridgestone Michelin Yokohama
Potenza G019 Grid Pilot Exalto A/S AVID ENVigor
Can you get cheaper tires? Sure. You could use the Kumho Ecsta ASX, Fuzion HRi, or the Dunlop SP Sport Signature which would definitely be less expensive.
Kumho Fuzion Dunlop
Ecsta ASX HRi SP Sport Signature
The real question is what are you giving up to save a few dollars. Normally the first characteristic to fly out the window is noise level, the second is wet and cold weather traction, then tread life and ride quality. Since every person tends to have different likes and dislikes it is hard to say what will suit your needs. Some people don't care about noise level. Some people don't care about tread because they just want the best traction. Some people want the best of all worlds and there are others that just want the lowest price.
In the end the most important thing a person should realize isn't necessarily just what fits and how much it costs. It's best to look at what will fulfill the needs you are looking for. If you're the one driving the car then you will have to live with that tire everyday. If the tire is for someone else and you are just doing the research and buying the tire for them, find out what type of driver they are and the conditions they are driving in to make sure that you will be buying a tire that will suit their need. Ensure you're happy with your tires for as long as they're designed to be driven on!