Data ARE data, but some data are false, some are misleading, etc.
There is nothing magic about having data unless you are on Star Trek TNG. I'm stating the obvious.
You might drop a cannon ball and a feather and generate data about the rate at which eat falls and conclude light objects fall slower than heavier ones.
You might look at the sun rising and setting and conclude it goes around the Earth.
You might make some measurement and get data and later realize your instrument was improperly calibrated. It happens. I have choked on my share of BAD data.