In the typical Web project, there are many steps to get your work done. You have to define the site structure, setup necessary modules, create content, make sure everything works, deploy, fix, repeat.
If you go global, the busywork gets compounded. You multiply your process by the number of languages, pages, words per page, people involved, steps involved and time zones. Some people keep track of pages in a spreadsheet, and every time a page changes, they have to copy and paste out the content, send it for translation and wait for the translation provider to email it back. Good luck avoiding errors in this process, too—by virtue of sheer volume, mistakes are bound to happen.