At the time of asking this question, the ED on Polkadot is 1 DOT and Kusama is 0.0000333333 KSM. Polkadot, and most Substrate-based chains, use an existential deposit (ED) to prevent dust accounts from bloating chain state.
https://wiki.polkadot.network/docs/build-protocol-info#existential-deposit
What are the metrics used by Substrate based blockchains when deciding on a specific value for the Existential Deposit? Would a situation arise when Polkadot or Kusama may have to change their ED values?