Complex sentence: In the early 1990s, Unilever's Persil detergent risked loosing its market-leading position as independent tests were showing the major brands to have relatively similar performance in removing stains, Unilever decided that they needed a product with an edge in stain removal.
Split into simpler sentences: In the early 1990s, Unilever's Persil detergent risked loosing its market-leading position. As independent tests were showing the major brands to have relatively similar performance in removing stains, Unilever decided that they needed a product with an edge in stain removal.