Why during chromatography must the paper NOT touch the sides

[jsmith613]

Homework Statement

why during chromatography must the paper NOT touch the sides of the test tubes in which the experiment is being carried out?

Homework Equations

The Attempt at a Solution

I am not sure but could our results get smudged or distroted?
if so I still can't work out how? could it be that the solvent does not run in a straight line :S

 

[chemisttree]

What might happen if the glass wall started wicking solvent from the chromatogram during the experiment?