I read somewhere that when a photographer (not a pro) accumulates more and more lenses and bodies, the actual act of taking photos becomes less fun. The idea is you get wrapped up in what to pick for a shot, not actually taking the shot. I've never been on the high parts count side of photography, so wonder if the idea is true. I only have one body and two lenses, so there is not a lot to pack or pick from when out in the world, and I have fun on every outing. If true, this could save me a lot of money in the future.
In thinking about it, if someone looks at a scene and thinks "which lens do I use?"I think this is because the person can't decide on the shot.
As was said, once you decide on the shot, the lens selection usually becomes easy.
I first start by elimination, then from what is left, the best fit.
If I want a wide panorama, I am not going to consider my tele lenses, I will look at what WIDE lenses I have.
If I am going to do a close up shot, it will most likely need a macro lens, not my tele or wide.
If I am going to do a tight head shot, it will probably be something around 200mm, not my wide lenses.
If I am going to do a full length shot, will probably be a 50mm, not my teles.
If I am going to shoot the soccer goalie on the other side of the field, it will be with the longest lens that I have.
If I need to use 75mm and I have two lenses with me that does 75mm, then it is a flip of the coin, which lens I will use. Other than bulk of the lens, it does not matter, 75mm is 75mm.
IMHO, they have not thought enough about the shot to decide what they want.
However, sometimes you are backed into a situation, where you want shot X, but only have lens A and B. So then the decision is which lens gives the the closest image to X and with what trade-offs?
Another situation is when planning a trip, and trying to decide on what 3 lenses out of kit of 10, to take.
But this is long before the shooting situation.
In can see this decision confusion more when buying a lens than using a lens.
Example1, do I get the 24-70/2.8 or the 24-120/4,
Example2, do I get the Tamron 35-150/2.8-4 or the Nikon 24-120/4 or the Nikon 70-200/4?