In other words, what we have experienced as product centric DNA can be a major inhibitor to sustained Solution Selling mastery. As we mentioned earlier, we have found that in the absence of formal, systemic reinforcement, the half-life of sales training retention is 30 days; within three months, 86 percent of knowledge can be lost. If the overall mindset and practices of the organization are highly product-centric, the reinforcement can actually be negative. This potential clash is depicted in Figure 4.3.