Paint flaking above skirting board - why?

[doglover]

I decorated our bedroom last year and I've recently noticed that the emulsion paint on the wall where it joins the skirting board is starting to 'flake'.

I'm not an expert decorator but haven't had this happen before.

Please could anyone shed any light on this? Should I brush the flakes away and repaint?

T.I.A.

There might have been some oil paint from the skirting on the wall above. Emulsion won't adhere very well to oil paint.