Whenever we’re looking at a migration we should always think about the agile/lean YAGNI concept. In pre-Agile days as a Project Dev Manager I would frequently say to teams “remember that when you move house that you take all of your furniture with you”. Often there would be situations where an upgrade or migration would result in some key feature being broken. But thinking YAGNI perhaps we shouldn’t expect all features and data to be migrated. That old tatty carpet that we’ve left behind, the things that are outdated or hardly used. We can think of YAGNI for both features and data – If your teams have accumulated massive backlogs do you really need all of that clutter?
The trick is to get a set of functions that cover the essential (MUST HAVE) operations and similarly the data that is required should be to support these MUST HAVEs. Other data could be reviewed/updated/archived as appropriate.
Think YAGNI – that’s the agile/lean way
Dave Browett-Agile Proj Mgt 
[…] The authors describe the delicate balance that the MVA has to maintain “…the MVA hangs in a dynamic balance between solving future problems that may never exist, and letting technical debt pile up to the point where it leads to, metaphorically, architectural bankruptcy”. As I’ve already mentioned, managing Technical Debt is a significant challenge and the more elaborate or over-thought the MVA becomes, the higher the Technical Debt overhead is likely to get. A key Agile consideration here is based around “YAGNI” – You Ain’t Going To Need It – which I first posted about over ten years ago! (https://davebrowettagile.wordpress.com/2013/02/28/yagni-means-you-aint-going-to-need-it/) […]