It's complicated. I live on a parcel of a very old property by US standards (early 1800s) that was subdivided shortly before I bought it. Without going into all the details, my neighbor who also lives on a parcel of the original land had a survey done and it turned out there were some significant incursions into other properties.

And we're not talking inches.

But, yeah, even inches (or any liens) can be an issue when it comes time to sell.