Let's assume you continually build and maintain a list to target prospects with email and more promotion on an ongoing basis. This process is automated, it's fast, but it's not a success. Drowning under a large and growing list, you have nothing to do but send out a generic pitch email to all. The dreaded email blast.
Your messages reach people who are at various stages in the buying process or, worse yet, are not true prospects for you product(s). This approach does nothing more than clutter in boxes and perhaps upset recipients that aren't far enough along to want email or other sales promotion. Management might be impressed with the sheer numbers, but they will eventually begin to wonder when they'll actually see results.
Once you understand the inherent limitations of putting quantity ahead of quality, you may want to whittle down your massive list to create multiple, granular lists ranked by "qualification." Ranking by qualified hierarchy can help you determine where and when to push your limited resources and focus with prospects at different stages in the buying cycle. This will set you apart to generate the results your management expects.