The Vammika Sutta likens skeptical doubt to a fork in the road. Say a traveler who is carrying many valuables arrives at a fork in the road; if he li… - Mahasi Sayadaw

One who fails to observe mental and physical phenomena every time they arise cannot see them as merely mental and physical phenomena. Furthermore, one does not realize their causality, impermanence, unsatisfactoriness, notself, or their immediate disappearance upon arising and their continuous disappearance thereafter. Therefore, one mistakenly identifies these mental and physical phenomena with a personal entity, a person who is either born without any cause or created by a creator. One mistakes them for someone or something permanent and pleasant, everlasting, and unchanging.

Sometimes the mind may wonder about practice itself. For example, the mind may wander off into analyzing whether an object was noted effectly, or sequentially, or vividly. The mind may wander off into thinking about how one is going to note an object. Under these circumstances, insight concentration cannot arise.

Ignorance immediately knows things in an ordinary, conceptual way. Because ignorance and its accompanying mental states arise first, wrong beliefs ensue. Therefore the texts say, "Ignorance conceals the true nature of obejcts."