LOS ARCOS MALL was commercially viable for less than 30 years. Its Broadway Southwest store went dark in January 1996, with Sears doing its "anchors away" in February 1999. The downward spiral of the complex had been exacerbated by competition from FIESTA MALL and SCOTTSDALE FASHION SQUARE.
Graphic 1 from L & B Real Estate Council of Dallas and Homart Development
Graphic 2 from Westcor Partners 

The final operational stores in LOS ARCOS MALL were shuttered in 1999. Demolition of the structure was done in stages between 2000 and 2002. The vacant site sat idle for years while a decision was made over what to do with the property. In the spring of 2007, SkySong, Arizona State University's Scottsdale Center for New Technology and Innovation, was officially dedicated.

Drawing from www.skysongcenter.com