Haha Gary! When you think about a telephone with 10 digits and the billions of phone numbers available, it helps to comprehend music possibilities. 4 chords create all sorts of possibilities when you think about adding 7th, 8th, b9ths, #9ths etc. Then depending on what progression (order), they are played in etc. The possibilities are endless.

Keep it simple and you'll be a big hit. You get too complicated and no one will like what you play but me and Chas. Haha.