I've heard from people who say they aren't always comfortable with the traditional element/direction correspondences. Some make adjustments to suit their own locations, such as a person who lives on the east coast of the United States may chose to associate east with water rather than with the more traditional air. It's hard to ignore a huge ocean to the east.
The most commonly used set of correspondences is: North - Earth, South - Fire, West - Water and East - Air. Why are these elements linked to these directions? It does seem rather arbitrary, even though many Wiccans and Pagans today use and accept them.
Many of the traditions of modern-day Wicca have developed from ancient Celtic roots. From people who lived in the area we now know as Britain, or the United Kingdom. So taking their geography into account, let's take another look at those
directions and elements.
West - The west is associated with water, as well as with changes, emotions, and healing. For Pagans living in the Celtic Isles, the Atlantic Ocean was a rather prominent landmark that lay to the west.
South - Fire was linked to the south for simple reasons that would apply to anyone living in the Northern Hemisphere: the weather gets warmer as you head south. Fire is associated with passion, strength and energy.
East - As I looked into this whole historical view of things, I found a few variations to why air and east might have been paired together. The sun rises in the east, which could be an association with air. Also thought is that weather patterns in the area brought many winds from the east. Qualities that go with East and Air are communication, imagination and travel.
North - The northern areas were more mountainous than the southern areas of the region. The craggy hills most certainly would invoke a feeling of 'Earth' to anyone who sees them. Earth represents nature, fertility and grounding.
But as I said earlier, not all modern traditions use these correspondences. I have heard that some associate north with air, rather than with earth. This could also be traced back to Celtic geography. The fierce winter winds would have swept the countryside from the north, making a very natural connection in the minds of the people.
Keep in mind that this is based on theory and speculation, and may not represent the actual reasons behind the traditional direction/element connections. You could probably come up with a dozen other reasons to link them in the traditional manner, and probably a hundred other reasons to link them in non-traditional ways. If nothing else, it might give you something to think about next time you are calling the Quarters.