Why does colour from my spray can match great when viewed from one angle and look awful from another?

Answer 1

This can happen if the panels that are painted are sprayed from different directions(on matalics or flip paints)and when reassembled the light reflects making it look a different colour even if it was sprayed with the same paint.

Answer 2

if its metalic paint it will be because, when you spray using a spray gun the spray head is magnatised to lign up the particals so they look uniform, obviously the spray can does not have this, so the particals in the paint will reflect light in different directions, most noticed from an angle.

Answer 3

I would suggest doing your match in daylight and not under artificial light as this will give a false perspective.