But it was her actions afterwards that were more concerning.
Judge Malosi said her initial action of dropping the hammer "fell at the lower end of the scale" but her "continued taunting" of her victim Dandi Wang had "moved to the medium level".
Judge Malosi said the woman posted multiple posts on her social media about what she had done. A year after the incident occurred, the woman posted a comment "commemorating the day of offending".
The woman also referred to Ms Wang as a "shameless bastard".
However, Judge Malosi acknowledged the woman had completed 35 hours of voluntary work and donated $800 to a charity.
The woman also attended two psychologist sessions where she was taught to deal with stress.
Judge Malosi said a conviction could affect her business ventures as the woman travelled overseas frequently.
"A conviction will place a stain on your otherwise unblemished record.
"You may not be eligible to travel at short notice as business dealings sometimes demand," she said.
The woman was ordered to pay $5000 in emotional harm to Ms Wang.
Ms Wang said she hoped the defendant, despite escaping conviction, learned a lesson and changed her behaviour as a result of the police investigation and court case.
"I'm still happy with the court because I don't want any bad conditions for her."
She said the hammer-smash incident was upsetting. "She should realise [that] she hurt me and [changed] my life."
Ms Wang said she was grateful to police, the courts, her psychologist and ACC for their help after the incident.
"I'm lucky I'm in New Zealand. The law can help me. The police can protect me."
Ms Wang was also grateful to her friends, family and her husband Xiao Yong Li for their support. "They supported me through a very difficult time."
An earlier Employment Relations Authority (ERA) decision awarded Ms Wang, a marketing manager at the television station, $15,000 for unjustified dismissal.
She was fired in March 2014 during a period of sick leave following the incident at the channel's premises.
In a dismissal letter, her boss accused her of failing to return company property and said a lack of a return date to work inferred she was "not capable of performing" tasks.
The station was ordered to pay her more than $10,000 in lost wages and holiday pay, as well as $8000 in compensation.
However, the amount was reduced by 20 per cent for Ms Wang's "contributory fault".