Final answer:
Inattentional blindness is a phenomenon where people can overlook objects or details in their environment when their attention is focused elsewhere.
Step-by-step explanation:
The question is asking what even the most careful person overlooks. One thing that many people overlook is objects or details in their environment when their attention is focused elsewhere. This phenomenon is known as inattentional blindness. For example, in a famous study conducted by Daniel Simons and Christopher Chabris, participants were asked to count the number of times a white team passed a basketball while a person in a gorilla costume walked among the players. Nearly half of the participants failed to notice the gorilla because they were so focused on counting the passes. This demonstrates how attention can influence our perception and cause us to overlook things that are right in front of us.