In operations, the bottleneck sets the speed of the whole system. You can improve every other step, but if the constraint stays where it is, total throughput will not change. Finding and relieving the real bottleneck is usually the fastest way to make a business move quicker.
Bottlenecks are often people or decisions, not machines. When decisions queue behind one or two people, those people are the constraint, which is how you get the founder bottleneck.