Upgrades tend not to impact end-users except by providing better user-experiences and a more secure protocol and perhaps more options for how to interact with Ethereum. Regular users are not required to actively participate in an upgrade, nor are they required to do anything to secure their assets. $DEGEN

The roadmap is mostly the result of years of work by researchers and developers - because the protocol is very technical - but any motivated person can participate. Ideas usually start off as discussions on a forum such as ethresear.ch(opens in a new tab), Ethereum Magicians(opens in a new tab) or the Eth R&D discord