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2. The size of artwork: Starting around 1990, "art “art was getting (literally) bigger" bigger” something for which Chelsea was "superior" “superior” (Molotoch, 530). Chelsea buildings often had garage door fronts and clear-through floors without columns. As Molotoch and Trekson write, "big “big space gave rise to big art just as big art demanded big space." ” Here is a photo from New York Magazine of a typical store/garage front in Chelsea – many of which have now been turned into galleries. It's It’s easy to see how this kind of space could accommodate large pieces of contemporary art. 
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3. Zoning: New York City designated art galleries in Chelsea as an "as“as-of-right" right” use in what was previously a manufacturing-only zone (Molotoch, 532). Chelsea is experiencing what Elizabeth Currid at USC would describe as the "active “active cultivation of art as a central part of economic development; " ” in other words the city wants to economically develop Chelsea with people, "not smokestacks" “not smokestacks” (Currid, 368).
4. Small Gallery Opportunities: Chelsea has many elite galleries. In fact, Chelsea galleries made up 63% of all New York galleries at Art Basel 2007 ( Halle & Tiso). But interestingly the "vast “vast majority of Chelsea galleries are small shops offering a series of opportunities . . ." ” (Halle and Tiso). So for the aspiring artist and aspiring gallery, Chelsea provides a lot of opportunity.
Whether Chelsea will retain its dominance over contemporary art galleries remains to be seen. Even though many thought Soho's Soho’s dominance for contemporary galleries would last forever, it didn'tdidn’t. And because so many (90% according to Saltz) of Chelsea galleries rent their space, there is no telling what will happen as more and more leases come up for renewal.