Your website requires a dependable web host if you value your time and content. With a commercial website, you could lose even more if your free or inexpensive webhost deserts you. Think about it - what would you lose?
Even if your webhost leaves you high and dry but you've backed your content up yourself, you'll lose prospects, sales, and your reputation while your site is down. Without your own backup of your web content, everything can disappear.
Many web hosting companies have come and gone, leaving their customers without a site until the customer can find a new service. Believe it or not, this happens every day. One reason for this is obvious. A free service may be only covering its expenses with advertising. Have you thought about this: customers need help?
A free or cheap webhost, by its very nature, caters to new webmasters, who by their very nature often require more time than those willing and able to pay for services. Just crunch the numbers. Your webhost charges you $4-$10 a month. You require maybe 20 minutes of a customer service rep's time in a month.
The webhost loses money unless they pay their customer service reps a very low wage, which in turn is reflected in the service you get. If such a web host wants to survive, they can either cut their services and therefore their costs, or they can start charging for a service.
Think about who else besides you uses cheap or free web hosting: porn site webmasters, spammers, etc. These are people whose activities, when reported to the proper authorities, can get a webhosting service blocked or shut down.
Either way, you have to realize that you are affected by how other people use the same service that you are using.
Remember, just like with any other purchase you make, you get what you pay for. Don't be fooled by web hosting services that offer you huge database storage capabilities for cheap. This is because data base storage is indeed inexpensive, but the service you won't be getting is what has real value - technical expertise; guaranteed uninterrupted, high-speed internet access; and quality customer support.