The now 30yo bought their first house say 8 years ago and the 2nd home now.
They could use non concessional contributions or simply have taken an interest in how their money has been invested.
I've added $1m to my Super balance this year and have not contributed a cent over my employer contributions. Just in capital gains in the shares I own.
Getting a high balance is not impossible. Most people are just lazy and take no interest in how their money is invested. Superannuation is likely to be the 2nd greatest financial asset they will ever have and yet they take zero interest in it except for maybe looking at the occasional statement.
