Some critical-process standards include a requirement for re-validation at “defined intervals”, and to require that those “intervals shall be justified”. (Language of ISO 11135-1, EtO Sterilization.)
It is common in the US device industry to regard the outer limit for 11135 re-validation as three years, with a maximum interval of one year between justification analyze (I have seen some places have their interval as “1 year”). Other validation requirements do not mention periodic re-validation. The purpose of this periodic validation verifies that the validated state is not compromised by any change that was not properly identified or evaluated.
Thus, to answer @Fady Khalla’s question: yes, it is necessary and it depends on the nature of the process and the applicable standard.

Quote from FDA’s Guideline
“The extent of revalidation will depend upon the nature of the changes and how they impact upon different aspects of production that had previously been validated. It may not be necessary to revalidate a process from scratch merely because a given circumstance has changed. However, it is important to carefully assess the nature of the change to determine potential ripple effects and what needs to be considered as part of revalidation”