Trying to understand everything about printing

I have an X Plus 3 and spend a lot of time in the slicer to make the print perfect. I notice sometimes when printing that an area is printed much slower than the rest. I can't see in the slicer any difference in that area. An example is a 0.8mm wall width cylinder 10mm high that was printed slowly the entire time. I'm certain this is for precision and I am definitely not a speed freak, I'd rather have great quality than a fast print. Can anyone shed light on why some areas are printed slower but those areas aren't differentiated in the slicer? TIA!