Hello Josephine. As in many things in Blender, it gives you lots of choices, you can use whichever you like most or feel most comfortable with. Try not to think about things as right or wrong in the Blender context, it’s just many many options and people get used to one and stick with it or change a habit once in a while. You can just use x-ray, but I like wireframe most, mainly because x-ray was a later addition and I was used to wireframe.
As Omar says it’s about choices/preferences. To add to that it’s also about older hardware. X-ray mode requires more resources compared to wireframe. Also personally with denser meshes wireframe is easier to see.
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