If you're looking to get the most from your employees, ensuring their happiness is a simple way to increase a variety of metrics including productivity, problem solving, creativity, and engagement. After all, employee happiness is contagious. (So is employee unhappiness.)
And because employee happiness is contagious, you'll find that happy employees improve your team dynamics. They work better with others, manage their emotions better, and are more enjoyable to be around.
If all of those other reasons weren't enough, happy employees also directly affect your business outcomes. Studies have shown that happy employees sell more, provide better customer service, and stick around longer.