Complex sentence: Because of this, Bean had to refund 90% of the costs of the first 100 sets of boots made, when the rubber on the bottom developed cracks Bean seemed not to mind returning the money, and the popularity of the boots was clear.
Split into simpler sentences: Because of this, Bean had to refund 90% of the costs of the first 100 sets of boots made, when the rubber on the bottom developed cracks. He seemed not to mind returning the money, and the popularity of the boots was clear.