Everyone has problems paying attention from time to time, especially when under stress or when having to attend to something that's not very interesting. But children and adults with ADHD have difficulty sustaining attention most of the time and they may present with a mix of symptoms of Inattention or Hyperactivity/Impulsivity.
What does ADHD look like? Inattentive Symptoms:
Being easily distracted, missing important details, forgetting things
Frequently switching from one activity to another
Having difficulty focusing on one thing
Difficulty sustaining attention to things that require a lot of mental concentration