• portability
• access to places that don't allow it
• weight (when hiking)
• mobility
  • in wildlife photography and other similar feats, a monopod is often good enough for long lenses
  • in sports, racing, birding, it can be easier to follow the action
• utility (as a walking stick)
• takes the weight off of big lenses (especially when the shutter speed needed is sufficiently fast for hand-holding)
  • sports (especially when trying to get a low angle for a good perspective and background)
  • airshows
• stick a flash on it and get off camera flash look without much setup
• get higher angles if you have a remote shutter
• defense

It can also be very stable if you use it correctly.

• portability
• access to places that don't allow it
• weight (when hiking)
• mobility
  • in wildlife photography and other similar feats, a monopod is often good enough for long lenses
  • in sports, racing, birding, it can be easier to follow the action
• utility (as a walking stick)
• takes the weight off of big lenses (especially when the shutter speed needed is sufficiently fast for hand-holding)
  • sports (especially when trying to get a low angle for a good perspective and background)
  • airshows
• stick a flash on it and get off camera flash look without much setup
• get higher angles if you have a remote shutter/use self timer
• defense

It can also be very stable if you use it correctly.

• portability
• access to places that don't allow it
• weight (when hiking)
• utility (as a walking stick)
• takes the weight off of big lenses (especially when the shutter speed needed is sufficiently fast for hand-holding)
  • sports
  • airshows
• stick a flash on it and get off camera flash look without much setup
• get higher angles if you have a remote shutter
• defense

It can also be very stable if you use it correctly.

• portability
• access to places that don't allow it
• weight (when hiking)
• mobility
  • in wildlife photography and other similar feats, a monopod is often good enough for long lenses
  • in sports, racing, birding, it can be easier to follow the action
• utility (as a walking stick)
• takes the weight off of big lenses (especially when the shutter speed needed is sufficiently fast for hand-holding)
  • sports (especially when trying to get a low angle for a good perspective and background)
  • airshows
• stick a flash on it and get off camera flash look without much setup
• get higher angles if you have a remote shutter
• defense

It can also be very stable if you use it correctly.