For the designer the drawing is the product of his/her mind sifting through experience and creating a style that can be constructed. No good having a nice idea if it is not possible to create or cannot serve the purpose that it is supposedly meant for. I must admit to not being a fan of some of the modern, and well known, cabinet makers ( one of the British royal family springs to mind) who produce highly expensive furniture that to all intense and purposes as only decorative use. Here are a collection of sketches showing the ideas before the final working design have been produced, thay are not as it were initial sketches , I am sure there would be lots of paper before hand, but they are certainly the sketches at a point when the idea has matured to form a clear vision of the finished article. I have found that I need to do sketches in order for me to think my way through the construction, it is also helpfull when trying to make an estimate of timber for pricing. The very act of putting pencil to paper allows the designer to go through a construction process and evaluate the possible problems.
This drawing of a steam packet deck chair, reminds me of one that I used to own and made several copies of it for friends and theatre, it uses very little timber, is very strong and folds neatly, as well as having, in my opinion, a very elegant appearance ( although this drawing is not probably the best illustration to support this). One of the copies I made also had a foot rest as part of it, this folded under the seat and had two small folding legs.