The things you focus on will grow.
If you are a Manager and you need to address a large group of employees and 10% are low performers, 10% are extraordinary and the remaining 80% of employees are somewhere in the range of “adequate to pretty good,” the goal is neither to praise the high performers nor to scold the low performers. You can do those 1:1 with the employees who need to hear your mind. Your goal (for the duration of the meeting) is to address the 80% of your organization that is somewhere in the middle. These are the people you need to motivate to go out there and be capable employees.
It’s not about motivating your superstars: they are already motivated.
If you focus too much on the “people who gave 120 percent” it embarrasses your superstars (who are on the edge of burnout most likely and wondering how long 120% is going to be the new normal) and makes everyone else feel that praise is unattainable.
It’s not about scolding your low performers.
Scolding seldom motivates someone to want to do better: at best it assigns consequences for their failures that they will want to avoid. If they knew how to succeed, they would probably already be doing that. Few people really are intrinsically lazy freeloaders or terrible people. Most employees with performance issues have barriers such as lack of training, personal life distractions, lack of clear goals, lack of functional workflows, meaningful feedback about their work that can be acted on, understanding of organizational culture & mores, etc. Sometimes it helps them to know that someone is watching and cares what they do, but generally it is better for morale if the someone watching is truly trying to help them succeed, not looking for an excuse to punish, shame or fire them.
If you focus on scolding the low performers, the Adequate 80% will worry you are talking about them and fret that Management is going to micromanage them, doesn’t appreciate what they do, is always demanding too much work for too little time/pay. Morale goes down as paranoia about the surveillance culture and punitive/disciplinary measures are threatened. If you are scolding everyone—even your Adequate and Great people, it creates a pervasive sense that there are systemic problems and everyone is a target. The problem will seem to be a lot larger because you were so upset about it you felt that everyone needed a good talking to about it. Everyone will wonder “is the Manager talking about me?”
Focus on telling your Adequate 80% that you have their back, that you are paying attention, that you will listen to their needs and remove obstacles and set reasonable priorities, fight for the resources they need. Tell them how proud you are of their commitment to their customers and projects. Tell them that they do great work and you want them to keep doing it. Ask them to praise and thank each other if possible, because people get attached to teams they work with habitually when they get recognition for good effort from their teams. Put your effort into telling people what kind of a team they aspire to be and help them get there.
People who gave 95-100% deserve recognition for showing up and getting the assigned work done without looking for glory or drama. You want them to come in to work tomorrow because replacing them is hard. Help them encourage each other to stay and keep doing the good work. You want them to keep the main part of the bell curve full, and you want the fullest part of that bell curve in a solidly effective place, not falling back toward your low performers just barely over the adequate line.
And then go deal with your disciplinary problems firmly but quietly. Discipline is loud enough without making a fuss over it.