Defining OOTB vs Customizations

[robynsah1]

We have several new developers that seek to have some guidelines as to what is considered out of the box functionality in Instanbul/Jaskarta versus what would be considered customization. We are trying to assist with defining this and putting process around our current developement methodology. Does anyone know or attempting to document?

[The SN Nerd]

These days I use the points below as a guideline to what is customization:

• Deviation from the State Flow as defined in Process Guides
  
  
• Modification to existing functionality

It's not just about wether something is a customisation or not. Other considerations include:

• When "extending the platform", is the feature you are developing on the roadmap for release by ServiceNow in future versions? 
• When "customizing", is the artefact you are customizing likely to be upgraded in future?