Pretty much the most important thing you need to consider is the web host's reliability. Can you think of anything more annoying than going to a store that is not open half the time? It is the same if your website is not reliably hosted. If you choose a host with lots of downtime then you're sure to win the race to losing the most customers the fastest. Do some research into hosts that you are interested in. Do they offer an uptime guarantee? Hosts offering uptime guarantees usually have the technology to back them up.
Another important thing you need to think about is customer support. Does the host you are considering offer 24/7 support? This is important because if anything happens to your website you can quickly contact them and get them to sort it out as quickly as possible. Personally, I prefer it if they have phone, chat and email support. Chat and phone support allows me to instantly be able to contact them if I have an important problem.
The last bunch of things you should think about are the features that you may need. You need to consider how much storage and bandwidth you need and whether there is space for growth and easily upgrading your plan if needed. Most hosts offer more than enough space to store your files but if you get a sudden surge in traffic, you need to consider bandwidth needs and how your host deals with exceeding bandwidth. Some hosts offer e-commerce ready plans that come with features such as shopping carts to help jump-start your business. Other features that should be thought about such as web traffic statistics, the number of email accounts offered, the type of control panel, supported scripting languages such as PHP and ASP, the number of mySQL databases offered and also software that is preinstalled such as forums, site building tools and blogs for those who aren't experts.
Think about what you need in a web host and then find a reliable web host that can support your online needs as a Webmaster. While its good to get cheap web hosting, I have made the mistake of getting cheap hosting and not getting reliable customer support and crappy features because I did not do the right research before selecting them. The host you pick will become your website's “legs” and if they aren't up to standard your website may fail.
