Photography is about light. It literally means drawing with light. For this reason the light quality is the primary factor of getting a good photo. There are two scenarios that come into play: the indoor scenario where the light is controllable (say studio) and shooting outdoors. In the latter one the situation is completely different as we are talking about lots of sub-scenarios: morning sun, noon/afternoon, overcast sky with clearly defined clouds, continuous clouds with no clear boundaries, magic sunset, fog, sky after rain and so on. The quality of light gets influenced by many factors which proves to be quite a challenge for the artist. Actually some photographers first carefully check the weather forecast in a specific region prior to going out in the field. A little pre-work might really make the difference!