I agree with watapki66 (sorry don't know your real name) Depending on the interest what you shoot so accordingly you buy a lens for it.
Exsample. I went to New zealand a few week ago and took my zoom lens too. Okay it is only  75 -300. I took about 6 shots all together. I don't think I am realy into zooming do I?

I shoot with my 17-85 a lot. If I would be richer I would have a 50mm prime and just use that. For macro I do have a dedicated 100mm macro lens.

seeyus  Tunde