People seem to collect lenses for bragging rights over function. You buy a bunch of lenses and before you know it, the majority will be sitting on the shelf or lugged around with you everywhere, only to never be pulled out of the bag.
A good lens makes a difference but you don’t need a huge variety to shoot better.
All my gear is Canon. I shoot with the Canon 5D and use these 3 lenses the most. In order of my favorite:
If you are shopping for your first lens, this is what I recommend based on how serious you are about photography (note: this is for Canon):
50mm f/1.8 – ~$100 – for the hobbyist
50mm f/1.4 – ~$369 – for the person who does photography jobs on the side
50mm f/1.2 – ~$1499 – for the full time photographer
If you can, I recommend getting a lens that is f2.8 or less. When I travel, I only bring my 50mmf/1.2 lens or the 24-70mm f/2.8 and no flash. But please note: If you are shooting a wedding, make sure that you have back up of all your gear!
By the way, in case anyone is wondering what the f-number is (i.e. f/1.2), it is the aperture. The lower the number, the better it is for low light and bokeh (creating blurriness in the background).
Lenses aren’t cheap so it’s good to take time in choosing. I recommend going into the camera store and playing with different ones because of course, people have different opinions as to what works best for them.