With new cameras coming on the market all the time, and so many great lenses available for them, it is quite tempting to amass a small army of lenses. When I still owned my 1Ds3, I had about 8 lenses. However… the more lenses I owned, the less I used my camera. I finally decided to simplify my lens lineup to just 2 or 3 lenses. I sold my 70-200mm f/2.8 L IS and 135mm f/2 L, and replaced them with a 70-200mm f/4 IS. I replaced my 16-35mm f/2.8 L with a 17-40mm f/4 L. I have been quite a bit happier with the f/4 glass because of the weight differences (though it’s not as big of a difference with the 17-40mm). I also sold my 24-70mm L, 300mm 2.8 L IS, and a few other lenses. Going back to the basics of a wide angle and a zoom has me more excited about photography. Plus, it was quite nice to cash out on the equipment that I was not using.
For new photographers, the prospect of owning a large number of expensive lenses might seem like a dream. However, I have found that the “grass is greener on the other side” analogy applies to photography. My own recommendation would be to stick with the bare essentials, the fewest number of lenses necessary for your own style of photography. I think you’ll enjoy it more.