If you’re 35 and you can put away the maximum salary deferral of $15,500 a year and you never change it (increase it), and IF you can earn an average 8% rate of return every year, by age 65 you’ll have approximately $1,827,927.
And that doesn’t count your employer’s match (if there is one).
unless you're a big shot lawyer or doctor or have a "pat" govt job, contributing to your retirement under age 24 is very unrealistic for our young people...they just don't have the money for it and the cost of EVERYTHING is very high....