About this question
I am trying to know the benefits of using Scratch.org for CI/CD. But the Salesforce document shows that the scratch org is the disposable and source-driven deployment of Salesforce code and metadata, designed for applying automation and programmers. But it also says that projects and scratch orgs can be applied by an individual. That is why there is no chance of merging or witness file conflicts.
[Reference](https://developer.salesforce.com/docs/atlas.en-us.sfdx_dev.meta/sfdx_dev/sfdx_dev_push_md_to_scratch_org.htm)
I think the Scratch org allows developers to perform pre-validation to avoid errors before the final deployment. Since asking 20 developers to push touched metadata for major releases into a Scratch org is not recommended, I think we should leverage the CI/CD tools for automating the deployment process against Sandbox org.
