If you are using a block plane the flat part of the blade is down. As the plane is used the backside of the blade at the cutting edge wears away especially when the plane is dragged on the backstroke. Then when the front side of the blade is sharpened a sharp edge can be created but the worn spot on the backside of the blade can still exist. Then when trying to plane the new sharp edge of the blade will not bear on the wood just the remainder of the worn surface on the back side of the blade. You must sharpen the front side of the blade until all of the worn spot on the back side is removed and the cutting edge is formed at the intersection of the flat surface and the face of the bevel.

: Polishing the back of the blade should be part of every sharpening cycle.

: The are a lot of sharpening methods and systems out there. There are almost
: as many styles and methods of edge sharpening as there are weight loss
: programs.

: It is easy to get confused by the tools and systems, oil stone or water
: stones,
: for instance and the mechanics of how to hone an edge.

: Just like strip building or anything else, too many cooks spoil the stew.

: Look through back issues or Fine Woodworking or pick up a book on the subject
: of
: edge sharpening with a method that appeals to you and FOLLOW the
: instructions.

: There are a sequence of steps you need to follow, to get into the habit of
: doing before
: you will be able to consistently produce a good edge.

: Ask people why they like oil stones or water stones or sandpaper on glass
: surfaces
: or whatever method you've heard of.

: Learn it, and habituate it.

: Rob