Excerpts from One to One:.

"As you know, the biggest problem in justifying information technology is not the cost of the technology itself, but the lack of a reliable way to calculate return on investment (ROI). Until now you may have justified most of your investments in computer systems by estimating the cost reductions anticipated. But the strategies we have been proposing generate benefits primarily on the revenue side of your profit equation, and this makes estimation more difficult-especially difficult, since the strategies themselves are new and different enough that the managers you put in charge of implementation are likely to have no real experience in them...

"In the long run, customizing your business to the requirements of individual customers will reduce your operating costs... An ATM that simply remembers individual customers' "regular" requests could handle many more transactions per day than one that treats every customer to the same stream of choices. To achieve this cost reduction sooner, focus your efforts on increasing the efficiency with which you match customers with the appropiate products and services."