In 2012, Blogger ended support for legacy accounts.
This year, we see that account recovery does not support legacy accounts, any more. People who don't remember their legacy account names / passwords are now unable to migrate - and are unable to recover account access, so they can migrate.
Every year, any account which remains unmigrated is less likely to be accessible, by the owner. As that happens, and with account recovery not working for legacy accounts, migration won't be possible - and the account will be unusable.
For many blog owners with unmigrated accounts, legacy account migration is simply not possible.
Migration may not be technically possible.
Thanks to a combination of account identity confusion, and plain old forgetfulness causing inability to remember necessary details, successful migration is unlikely.
Add to those issues the general confusion about which accounts require migration - and we see the wisdom in Blogger dropping support for migration, in 2012.
If you need to migrate now, you may have waited too long.
If you have a dormant Blogger account, which may or may not be in need of migration, and you now see the need to migrate but can't, we feel for you - really. However, your inability to migrate now is a direct result of your inattentiveness 2010 - 2015.
You should have migrated, by 2012. You ignored the repeated warnings - or maybe did not receive warnings, because of intentional or un intentional anonymity - and 3 years after migration support was ended, you are finally seeing the handwriting on the wall.
Unfortunately, it's simply too late. For some, 2012 may have been too late - and now, in 2015, it's too late for too many.
Some may manage to migrate, with enough effort - others may not need to do so.
It's possible that some folks may be able to recover / remember the necessary details, given enough time researching. And others won't need to migrate - though they may not realise that detail.
And too many simply won't be able to migrate.
If you do have a legacy account, yet unmigrated, you may want to consider an alternative policy. Time is not on your side - and it may simply be a waste of your time and money, to attempt migration.
An Important Update
If you did not use a Blogger / Google account when you Followed this blog, years ago, you are probably not Following now . During the past...