When a whitehead is in the early stages of forming - that is, only a whitehead has formed but no major fluid build-up behind it has occured - frequent washing as described in Cleanliness for General Acne Prevention will often weaken the skin enough for the whitehead to come out and then the skin will heal itself.

A very small scab therefore often occurs during the healing stage, but it is quite minor, heals quickly and leaves no discrenable scar.

When the whitehead is more developed - that is, with fluid build-up behind it - cleaning alone will often get rid of the top whitehead, but the resulting small wound will not heal well and another whitehead often soon forms.

This is because either the fluid behind the original whitehead re-blocks the pore to start the whitehead formation process again, or more usually a secondary blob of whitehead material has formed further down the pore and once the top whitehead has gone, the lower one can make its way to the surface to greet-the-world, or re-block the pore further down creating a reddish dome on the skin surface.

Unfortunately, squeezing of whitehead acne often becomes the only way to ensure that re-establishment cycle is broken, so the pore has a chance to heal itself, then have cleanliness used as the first line of defense against whiteheads forming again.