Asset management is an issue every digital photographer grapples with sooner rather than later. You could dump everything in one big folder on a hard drive, that's asking for heartache. Not only is it tough to lay your hands on specific photos, but unless you back up regularly, you could lose every one of those images if the drive fails.
And what about image editing and versioning? Color management? Assigning metadata? File formats? The deeper you get into working with digital imagery, the more workflow questions you have.