People with ADHD are immature
Executive function is located in the prefrontal cortex which doesn’t fully develop in adults until around the age of 25. In people with ADHD, this can be delayed by up to 30% and can still be impaired after development.
This can lead to people seeing people with ADHD as undisciplined (rather than suffering from a medical issue) creating a societal stigma around treating the disorder. This can lead to self-worth issues.