That is a good questions. Some customer’s strategy is to keep it simple and stay on the version that is currently installed. They run their enviroments with the motto: Never touch a running system.
Problem is, these customers will not benefit from security patches, bug fixes, better performance, better functionalities and the benefits new functionalities gives tehm to ease the administration of their infrastructure.
Next, the HW vendors changes their HW components within the systems faster and faster. OSes have to support the new HW. So we have to install new versions. Buying new HW means, to get better performance, better security and new functionalities and features.
All in all, once we havt to update our environment. We cannot stick to one version.
A colleague of mine gathered arguments, why you should once update to ESXi 6.5.
What do you think? Will you update? When will you update?
VSphere 6.5 provides alot of new features to enhance your feature set with important security functions, to increase the availability and realiability of your environment. And this mitigates risks!