Interestingly enough, this thought comes to me as I'm devouring my dinner at a local buffet-style restaurant establishment. Maybe it's due to the influence of the Food Network, but it seems as if I have recently trended towards explaining technical concepts with food analogies.
Quality data fulfills the business' needs. Where as, mass quantity of data may satisfy the end-user's wants. Of course there are trade-offs!
Sure, while standing in the buffet line, if I'm asked what I want, I'll ask to have food items piled on to my plate overflowing onto my tray. However, when I sit to consume the food (read: querying data), it takes longer toload it all off of my plate and into my mouth (read: generating report), to the extent that I'm becoming groggy and sluggish (read: lag in rendering output).
Optimally, to enhance the efficiency of my metabolism, I would be wise to avoid the buffet, and stick to ordering a la carte... to simply fulfill my needs by eating a sensible meal as to increase performance (read: selecting quality data pertinent to fulfilling needs instead of going down the route of, "just pull all available data and I'll just look for what I need").
I'm sure those who've had to gather requirements for reports have come across this scenario often. The user experience is hindered by the time it takes to generate the output because the requestor didn't initially take the time to isolate pertinent target data. Again, one of those cases of, ""just pull all available data, I want to see everything."
Understanding the needs vs wants up front will help avoid potential performance frustrations later by reducing the quanity of data to quality data. In the end, a well balanced meal is satisfying and healthy; a well balanced report is fully informative and actionable.