That was my experience yesterday, when I tried my hand at baking and decorating a cake for my sister's baby shower. It took four hours! Before I got started, I hadn't really understood what I'd gotten myself into. Normally when I bake a cake I get some cake mix and a tub of icing and I'm done. This was a lot more complicated.
The cake was easy, but the icing was made from a mix, with dye added to create the different colors. Then it was put into a piping bag, each one with a plastic spacer which would hold the metal tips. After getting all the icing prepped (including a trip to the store for my icing an dye colors), I was ready to be done. When I finally started icing the cake, I had to work on my technique and it was never perfect. After a while of constantly squeezing the piping bag, I found it hard to open my hand!
Eventually, after four hours of work, the cake was done and I had a new respect for the cakes my Grandmama used to make for us when we were kids. And she would do two or even three in a day!