Sometimes data is needed first in order to understand what is possible. Why limit ourselves to the imagination of the chief architect?
Once the data is available it can be viewed from multiple statistical viewpoints for various stakeholders, who, from experience, will only "see the light" once it's in front of them.
Correlation may not equal causation, but quite a few times it does and with some pier reviews the assumptions can be vetted.
No data will give you no information.
Once you do get data, for example room temperatures, you can start asking questions like "what is the average temperature of this room?", "why do I get a spike at 6 am every week day?" and most importantly "what happens if I change this?".