Agreed, I do not see much value from selecting an alternate source from the same company. I also do not see as much value in selecting a second source all the time for critical components. Other measures can also be looked into such as ensuring there is sufficient safety stock of a same component within your own inventory. Typically what I have seen is that companies will place large rounds of POs ahead of time to ensure there is backup product in case a supplier is not able to deliver at the time an order is placed with them due to severe circumstances. Qualifying a separate overall supplier that can manufacture almost exactly to spec of what you wanted in the beginning is a more efficient alternate method to ensure you will always have a reliable source of product rather than procuring another similar product from the same company.