There are many reasons to migrate your mailbox exchange to a new computer. First of all, you have no more space on the existing server, so you need to migrate your email exchange to a new server. Or you have a new mail migration strategy, and you want to change your email address. So the first thing you need to know is how to migrate email from the exchange server. If you want just one email server, move your current exchange server to a new computer. The other way is migrating exchange with a third-party tool. It has good features like bulk migration, easy configuration, and reliable services.

Software for Exchange recovery and Migration: Exchange Migration tool | Exchange Recovery

According to this article, 6 reasons make businesses nervous about Exchange Server migration. One is "The risk of downtime or a service interruption during the migration period."
So, companies are moving their data to cloud data storage which is better and fast.

Migrate Exchange 2010 to 2019

Migrate Exchange 2013 to 2016

Migrate Exchange 2013 to 2019