I think it can often depend and can be a double edged sword but perhaps the key would be showing progression in your skillset in later projects. If a project worked well and you can talk through your decision making then to redo some sketches I think is a bit of a lie because that isn’t really how you got from A to B at the time. On the flip side though, when someone sees hundreds of folios that bad bit of work you did in school may now not be where you are currently in your career so it could end up costing you an interview. We do work in a fickle industry.
I have a project in my folio (it’s getting close to being pushed out mind) that is one from school but I completely redid it at a time when my skillset had vastly improved. The final design still had the same thought process and function as when I handed it into my tutors but I completely redesigned it right from initial sketches to polished CAD/renderings when I had a better appreciation for form and manufacturing.