It is not unusual for me to hear people say that they don't feel like they need to have data, or quantitative information generally, inform their decisions.
Most of me thinks that is unwise. But I also understand their perspective, even if I don't agree with it. Sometimes the evangelists of "big data" promise things they can't deliver. Sometimes they have a misplaced idea of where data should be placed in their decision-making processes. Sometimes they just have a very narrow definition of data that prevents them from preaching its true worth.
My definition of data is "Information, mostly quantitative but sometimes qualitative, that can be organized in a way to see trends, judge performance, increase efficiency, and otherwise aid decision-making."
This is a fairly broad definition. Survey and polling results fall within this definition. So do results of experiments of varying levels of complexity. Self-reported data from employees qualifies. So does website and social media data, fundraising and other financial data, and field contact data. Publicaly available data, of course, qualifies.
I could go on and on.
There are pieces of information, though, that cannot fit easily into this definition, if at all. Some aspects of relationships are not easily categorized or quantified. There is no replacement for expertise or a wide network of contacts. Also, the general zeitgeist is almost impossible to measure.
However, deciding not to use data because it can't give you everything you want is "letting the perfect be the enemy of the good." This is especially true when it comes to tracking, and using, data to manage people and improve organizational effectiveness.
For example, tracking one-to-one conversations held by members of the sales team can allow a manager to coach her employees to make the most of potential leads, while halting or limiting time spent on leads that aren't producing sales.
The manager would be wrong, though, to only look at the numbers and then order the sales rep to halt all work with a lead. It might be that the lead wants to switch suppliers, but has the wait until the current contract runs its course. In this situation, the sales rep is doing the wise thing; maintaining a relationship that will produce sales down the road. The quantitative information prompts the manager to ask questions. It isn't the end of the decision-making process, but the beginning.
This type of process is also useful in community organizing. Managers can see how many one-to-one conversations organizers are having per week. They can see who those people are, and if they have taken any actions (house meetings, legislative visits, phone banks/door-to-door canvassing, etc.) If an organizer if spending a significant amount of time with an individual who is not taking next steps, the manager can ask the organizer what is going on.
It might be that the potential leader is going through a divorce/death/job transition/etc. They could have all the characteristics of someone who will be great, but life is just getting in the way. In that situation, it might be worth it for the organizer to continue working with the individual even though s/he isn't currently taking action.
However, it could also be that the two have become friends, but that the individual will never do more, and the organizer is blind to it. The manager can then challenge the organizer to spend less time on that relationship.
Regardless of your situation, if you aren't tracking your organizational activities in comprehensive and meaningful ways, you are robbing yourself of valuable information that can be used to make your work more efficient. On the flip side, data can't save you. If you don't know your field, stakeholders, clients, constituents, or customers deeply, or if your organization is deeply dysfunctional, then terabytes of data won't make you successful.