A good way to apply the ITIL guiding principle 'focus on value' is to:

The ITIL guiding principle ‘focus on value’ states that everything an organization does should link back, directly or indirectly, to value for itself, its customers, and other stakeholders1. A good way to apply this principle is to understand why services are used by service consumers, what outcomes they enable, and how they contribute to value creation2. This helps to align the service provider’s activities and resources with the needs and preferences of the service consumers3. References: ITIL Foundation - ITIL 4 Edition, page 6; ITIL® 4 – A Pocket Guide, page 24; ITIL® 4 Practice Guide: Focus on Value, page 9.