depends on usage. if you don't manage your storage space wisely, it can get to the point of being full of bloatware, duplicate files, etc.... to prevent wastage of file space, do weekly clear cache, and maybe even once a year do a full factory reset and restore the apps you do use via titanium backup.
also people who tend to prefer keeping their media on their smartphones run the risk of storing too much such as videos, and music

So for the heavy users that don't want to rely too much on off-site stored media e.g. NAS, CLOUD etc... they will use an EXTERNAL SD 16-64GB to store their excessive media files and apps using .....
Link2SD
https://play.google.com/store/apps/details?...e=search_resultor alternatively DirectoryBind
The S3 camrecorder also has the potential to quickly use up your finite storage space. As a real life example, this is my camcorder stats i got using media player classic

the S3 international only has 16gb internal of which roughly 50% i've already used. So that is like 8GB of recording time, unless i opt to buy an external SD 32-64gb to offload the increase file size because of a higher bit rate setting.
I'm using a cam mod which has a 30mbit rate compared to the stock camera limited to roughly 16 mbit i believe.
http://forum.xda-developers.com/showthread...=1883192&page=5Do u able to use Link2SD to move apps to external microsd? I tried but can't.