Not following the PDCA cycle?

Answer:
The PDCA cycle is embedded in the way ISO 14001 was written. If someone does not follow the PDCA cycle it will, most likely, be inefficient and ineffective.
Following the PDCA cycle is a way of trying to avoid a situation where something not needed is done. The PDCA cycle help us start by where action is needed. If an organization does not follow the PDCA cycle it can do a lot of work, use precious resources, and getting progress in areas where there is no priority for change.

Following the PDCA cycle is a way of promoting continuous improvement because the end of a cycle can be the start of the next one.

The following material will provide you more information about the PDCA cycle:
Article - Plan-Do-Check-Act in the ISO 14001 standard - https://advisera.com/14001academy/blog/2019/08/27/key-iso-14001-benefits-to-customers/nowledgebase/plan-do-check-act-in-the-iso-14001-standard/
Enroll for free in this course – ISO 14001:2015 Foundations Course - https://training.adviser a.com/course/iso-14001-foundations-course/
Book – The ISO 14001:2015 Companion - https://advisera.com/books/the-iso-14001-2015-companion/