OJT(On the Job Training)
Onboarding is the process that helps newcomers quickly learn and adapt to the organization's culture. "Welcome on board" means "We welcome you to the company." The meaning has expanded beyond just new employees to also refer to new software customers, where sending easy onboarding emails to customers is recommended.
It's very important to have people who haven't used your company's product try it out and get feedback from "fresh eyes." This could include employees' children or as diverse a group as possible.