non-mandatory

the training session was non-mandatory, but highly recommended for all employees.

attendance at the team-building event is non-mandatory, so feel free to decline.

the overtime hours are non-mandatory; employees can choose whether or not to work them.

wearing a uniform is non-mandatory for new hires during their initial training period.

contributing to the project is non-mandatory, but your input would be greatly appreciated.

the safety briefing was non-mandatory, but we encourage everyone to attend.

joining the optional excursion is non-mandatory; it's up to each individual.

submitting a proposal is non-mandatory, but it can increase your visibility within the company.

volunteering for the task force is non-mandatory, but valuable contributions are welcome.

attending the after-work social gathering is non-mandatory and purely for enjoyment.

providing feedback on the new system is non-mandatory, but helps us improve it.