Skip to the section on Process, if you do not need to know why consolidation of a wallet is necessary.
The basic idea of an unspent transaction output blockchain is each transaction has inputs, which are a series of boxes. A transaction then changes those inputs and create new boxes as outputs.
A blockchain wants a record of transactions, but it does not need to keep the old boxes on the blockchain. Ergo addresses this problem with a process called, Storage Rent. After four years, old boxes that are taking up space are charged a fee, and if there is no fee, these boxes are deleted from the blockchain.
This helps keeps the blockchain size smaller. It makes sure that all Ergo coins stay in circulation, say when someone forgets their seed phrase, those Ergo coins eventually will return to circulation. It also serves as an additional source of income to incentize miners to secure the chain beyond initial emissions and transaction fees.
If you use Nautilus, send all assets to yourself in one transaction.