Salesforce Lightning migration from the Classic Edition is inevitable for users. The questions is not whether to migrate to SFDC lightning or not, but when to do it. Read about what is Salesforce Lightning Experience, whether Salesforce classic is going away and getting started with the SFDC Lightning migration.
Salesforce Lightning is an upgrade from Salesforce Classic, which can be described as a step change, and not just an incremental one. It upgraded the look of Classic UI and more importantly, it upgraded the productivity for the individual user. When the migration is carried out to leverage the real transformational capability of Lightning, it is essentially a re-implementation of Salesforce. You don’t have to import your data, recreate your custom fields, or set up your security model. However, everything else may need to be revisited with a fresh lens, including:
