Startups often treat every customer the same for customer acquisition cost (CAC) purposes, which is a mistake when scaling.As startups expand into new market segments, new verticals, and new buyers, the CAC will be higher in those areas.A framework is suggested where 80% of new customers should hit sustainable CAC goals, while 20% should break even to enter new markets.It is important to give new market segments 24 months to reach the same CAC efficiency as the core.