Very simple. Discipline should come from inside... within. Kids are sent to school in an unformated format. Learning discipline starts from there. Beyond schooling, it is for the grown up adult to understand the advantages of being disciplined. Once at work, people learn and understand the advantages of being punctual, following timelines. Beyond giving punishments, the leaders, the seniors, the HODs, the CEO etc should lead by example, by themselves coming to work 15 minutes before the start of the day. That will set a good precedence. While they are young, parents create precedence and they become role models and at work, the seniors play a significant role in establishing discipline, ethical practices etc. In my training module on Ethics at Workplace, I tell the participants that if you are not punctual or not spending quality hours at work tantamount to Unethical practices.
Best wishes