Failures and mistakes, relationship friction, duty and responsibility, increased pressure and ticking clocks, loss of control, power struggles, ego-related conflict

This entry explores scenarios where the character was specifically being counted on to perform well, but they dropped the ball. For more general information involving a character failing to meet the expectations of others, see DISAPPOINTING SOMEONE. 

The character not following through on a promise to attend a child's concert, a parent-teacher meeting, etc.
A spouse forgetting their anniversary or their significant other's birthday
Being a no-show as a conference speaker because the character had the session's time wrong
A student not completing their portion of an important group project 
An athlete making a critical mistake that results in a loss for the team
Working late and missing an important family celebration
A character who is part of a best friend's bridal party getting drunk and missing the whole thing
Not preparing enough for a crucial meeting and being unable to answer vital questions
A contractor failing to provide the level of quality that was promised in a product or service

Having to sit through an interrogation over what happened (reliving the failure)
Being criticized, yelled at, or threatened
The character and their group receiving a failing grade on a project
Losing an important client 
Disappointing a child or spouse 
The character earning a reputation for being flaky
Losing an important game that would have moved the character's team into the finals
The character enduring verbal abuse because of their mistake
Being constantly reminded about important events by family members who no longer trust the character's word that they'll be there
Being questioned constantly about future commitments: Will you remember? Can you handle this? Is it written in your calendar?