It is important to understand the difference between observation and perception.
Perception is what we BELIEVE we see, whilst observation is factually, and legitimately what we see.
The problem with relying on our perceptions of certain things is that we tend to attempt to come up with our own conclusions for the purpose of fulfilling our curiosities, it's only human nature to do so however it is incomparable to a hypothesis, or prediction.
I hope this helped, it's a little short so my apologies
