In the early 2000's I discovered Irfanview, and used it because it was lightweight and loaded jpeg's much faster than anything else I was using at the time - this was on a 133Mhz Pentium 1 running Windows ME with 56MB of RAM.

I also like Irfanview because:

A) It has every basic editing function you might need (crop, color adjust, blur/sharpen), great for ad-hoc one-off things. It has all these functions but loads just about instantly on my older laptop. For example, if I need to rotate a picture real quick, it's convenient to open it in Irfanview and just press L/R to orient it.

B) I like it for one-off converting pics from one format to another, and it's the only GUI program I've seen that lets you save as jpeg, but also specify the target size. So I can convert a 10MB PNG to a 256KB jpeg easily. I know this is trivial to do in Linux with the convert command but when, for example, working with pics from my phone, I'm already previewing it in Irfanview in the first place. Irfanview's save GUI actually exposes a lot of knobs for many image formats that I don't see on other programs.

C) If you want to extract images from a PDF, you can open the PDF in Irfanview and Irfanview will let you save out the individual images. At least for the PDFs I've tried it with.

D) The batch mode it has is decently implemented and is easier to use than Linux command line stuff for small jobs if Irfanview can take care of the need (less than 50 images), especially if the images are all over the place and not in one folder.

I'm so used to it I'll probably use it in Wine (if possible) if/when I actually make the jump to everyday desktop Linux, which Windows 11 may make me do finally.