One advantage of using a single-source supplier strategy is that it will

One advantage of using a single-source supplier strategy is that it can help reduce variation in the materials or products supplied, including lot-to-lot variation. When only one supplier is used, it ' s easier to work closely with them to ensure consistent quality and to address quality issues that may arise.

Supply chain management and quality management literature, which often discusses the trade-offs and benefits of different supplier strategies, including single sourcing.