Here are 2 things that are true, but are seemingly contradictory:
You must cross-train your employees. Perhaps everyone on your team should know how to close customer support tickets and can be called in to support the customer service team, when needed.
You must assign ONLY one role (which might be more than one person) to own every task in your business. Because if everyone on the team is accountable for closing customer tickets, you’re at risk of it not being done reliably.
When you don’t give your team clarity on who owns which tasks, balls get dropped, toes get stepped on, and processes don’t get innovated.
Cross-training is to provide backup, not to forever distribute the workload.