I have about 10
$.getScript(...) jQuery method is asynchronous, and therefore it will not retrieve your scripts consequently, resulting in the scripts being loaded in a random order (e.g. "script3" gets loaded before "script1"): so if any code in some of them relies on previous scripts there's a high chance that it may go completely wrong and fail rising some
TypeError for undefined variables.
To make sure your scripts load in the correct order you can make synchronous Ajax calls, like this:
but this will obviously slow down your page a lot, freezing it until all the scripts are loaded. By the way there are some good libraries (e.g. RequireJS which relies on jQuery) to load scripts asynchronously in your page at any time, even though IMHO I wouldn't feel very good about using them.
To answer your question: if you don't want to use external libraries (with dependencies) it's better to keep the scripts in the body of your document: it makes them load faster and doesn't require additional effort.