These include the large middle-class suburbs of Peoria, Mesa, Chandler, and Glendale; upscale Scottsdale; and the college area of Tempe which serves as home to Arizona State University. All areas are modern and generally lacking in historic interest, but keep in mind that Phoenix only had 100,000 residents in 1950.
do {} until ($false) is an infinite loop; it'll only exit if you use something like break, return or throw from inside the loop body. do { } until ($true) would execute the loop body exactly once (which would make the loop rather pointless.) It looks like what you intended to do was wait for a file to exist.
Code placed between Do Until and Loop will be repeated until the part after Do Until is true. Explanation: until i is higher than 6, Excel VBA places the value 20 into the cell at the intersection of row i and column 1 and increments i by 1. As a result, the value 20 will be placed into column A six times (not seven because Excel VBA stops when i equals 7).