I love them mostly because it gives me something to do with my hand while hiking haha. I’ve heard other people feel like they can walk faster without them (these people had really light packs)
I have used poles for hiking and trail running and my experience is that they are helpful for terrain where my footing might be a bit unstable, or if I can use the strength of my arms to take a little work off my legs. I have a pair that folds down so when I don’t need them I can store them pretty quickly so that they aren’t a tripping hazard when I don’t need them. I do also like them to help distract me on a long section of trail - something for my hands and arms to do! I hiked the Loowit Trail around Mt. St. Helens last summer and they were especially helpful on lava rock fields where stability was tough, and on steep inclines where my arms were helping me out. That is my experience with trekking/hiking poles and hope it helps.
This is always an ongoing debate for me… I like to take a hiking stick but it does often become cumbersome which defeats the purpose. So if I know there will be any scrambling I won’t take it. Poles really come in handy in this case and I like them for that but I haven’t found a set I truly LOVE for my grip so I have found I use them less than I should probably.
I need them for big mountain hikes. Playing sports my whole life left me with bad knees so going down they are crucial in my stability. I don’t bring them if i’m just out for day hikes, but I do for all backpacking trips (in case I need quick shelter set up) and for big mountain hikes.
I have never gotten the hang of them. The only time I’ve felt a benefit is when I was coming down a 14er after an exceptionally grueling hike up. My knees appreciated the relief of having the bit of cushion they provided.
Yes - really saves on the wear and tear of your knees, aids in the upper body workout to. If you go ultralight can be used as tent poles. Good for balance on tricky parts of trail. There is even a camera mount you can get for some brands that is a nice bonus.