I have a series of paper sketches done as part of my design process. As I take the design to the next stage I am creating a better representation of my design that builds on my sketches and will eventually lead to my final design. Do you discard rough product sketches? Some of my sketches are very rough and I feel as if it might help me to discard those I didn't take forward in order to hone my final design. At the same time I would like to keep at least an example of my thought process in a coherent / well presented way.
Never discard sketches. They may contain ideas and inspiration for other projects or even later versions of the same project. At the very least, you can reflect on them later and be inspired for new work.
They can also serve to illustrate a point when presenting your work. For example, if a certain shape or other decision seems a very obvious obvious choice that the client will probably expect you to make, it may serve you well to show your sketches of that idea and use them to show why you didn't go through with that line of thought.
I use a journal to sketch in, and even doodle and make small notes. I've gotten so used to having a repository of old ideas and doodles around, that I feel lost without it when starting a new project. When I've been doodling on a loose piece of paper, it even pains me to throw it into the bin!
I just bumped on this thread while i was working on a project and i thought it was worth answering to your question.
It's a real coincidence because in the contest i've just joined, the Contest Holder is specifically asking to show the work in progress from sketch to digital. I will not only keep the sketches, but add screenshots of my work in progress too.
IN my practice i do this not just to show that the work it's mine and original, but because i want to show the potential client the process my artwork creation.
1) The client get a better understanding of the work process and the amount of work i put in my job (sometimes underestimated from clients).
2) I think this part of the process can help both client / designer in case of changes are needed as the client has a better vision of the whole work so that the changes can be done quicker and more efficiently.
3) I agree with Vincent post. I myself get a lot of inspiration from old sketches i used for other projects. Sometimes i take 1 or more elements of a particular sketch or i redraw the same sketch again and in the process a new illustration come up.
4) I keep everything rough and better sketches. I leave my sketches close to my desk on top of a shelf and easy to access. This is important because it's quick to review them. If i don't use this system it would be too annoying and wasting time to look for all the doodles around the house and i'll end up never looking at my old works.
The only downside of this process is that my studio has paper flying every where! So once in a while you have to tide up because your work environment can become very messy... you'll drawn in paper!!!
This is my 2 cents. I hope it helps.