Moving data between tiers of storage has gotten easier as a result of global file systems and simplified archive software. But upgrading to a new platform that is just plain ugly. The more data there is the harder it is to move. This data has to be moved in such a way as to preserve file security attributes while at the same time optimizing performance. The big challenge is that the storage may not go all the way up the manufacturers product family. So, for example, if you purchase a midrange system you may not be able to take your data with you.”]
Source: https://www.darkreading.com/database-security/migration-migraines