Untagged ways

When mapping I sometimes come across ways without any tags, often along roads that have or have not been mapped already. Sometimes I use them as just another public track, sometimes I convert them into the road I believe is there, but I am not quite sure what is the preferred way to deal with them:

Is somebody in the middle of mapping something and I should leave the way alone?

Should the way be deleted, after the road, or whatever is there, has been mapped?

Should they be considered as reliable as uploaded GPS tracks?

Any ideas would be appreciated,

Jochen

You can have a look at its history to see when it was last modified.

No, GPS tracks are the source for ways, if there are no GPS tracks there, there should be no way.