I'm going to put my foot down on this one: >90% of "we need a new Salesforce Org" should be a cleanup and focused refactoring effort instead.
A new Org sounds attractive. Fresh start. No technical debt. No clutter.
In reality, most of the time you're rebuilding years of business knowledge, revalidating processes, retraining users, recreating integrations, and introducing significant delivery risk and not to speak of the immense cost on the whole organization like training, change management etc.
A focused cleanup and refactoring program is almost always faster, cheaper, lower risk, and delivers a far better outcome. Keep what works. Remove what doesn't and clean everything else. (Simplify. Standardize. Modernize.)
Yes, there are cases where a new org is the right answer (e.g. Agentforce Life Sciences implementation in 50 countries), they're just far less common than many people think.
The highest ROI Salesforce transformations I've seen wasn't a new Org. It was a disciplined cleanups, the biggest waste of money I've seen were a re-implementation of a dirty Org in a new Org, just to end up copy/paste most of the dirt.
PS: Thanks for the conversation around that topic Maham Hassan
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