National Assn Of Realtors: Inventory of for-sale homes on the market has fallen 24 percent from a year ago and many are pointing to the “immobile move-up buyer” as the reason behind the drastic drop. Some analysts say the lack of move-up buyers in the market may also slow the overall housing recovery.  

Housing affordability—due to fallen home values and ultra-low mortgage rates—is at record highs. But mortgage applications for home purchases are down by 6 percent over the last year, according to data from the Mortgage Bankers Association. 

Some point to the still-high number of home owners underwater on their mortgage as the reason. Many of these home owners are taking a “sit and wait” approach until prices pick up. Only then will they seriously consider moving on, analysts say.