The most common method of transferring Web pages/ files from a computer onto a Web host is via FTP. The problem is, many free hosting providers do not offer access to FTP.
More often than not, these hosts offer only online site builders. Although these are obviously great for novices, unless a site is exceptionally trivial and will never need to be expanded or improved, FTP access may - or should I say invariably will - become necessary at some point or another.
The online site builders typically offered frequently leave a lot to be desired, and may not actually include all the options/ features a user may require. In addition, they often provide users with very little control over their site and can be inflexible to say the least.
What's more it is often difficult - if not impossible - to transfer a site to another host if the need to do so should arise. Many free hosts lock sites into their services, and templates used to build sites are copyrighted, making it impossible to transfer them onto another host. This, of course, means if a site's requirements outgrow the original free host, it will have to be completely rebuilt if taken elsewhere.
In short, it is elementary to ensure that even when a site builder is offered (and tempting), the ability to access/ modify your site via FTP is also provided.