Please get this right, people.
Juggernauts barely have a lot of hard CC, not a lot of mobility, and not a lot of gap closers. However, that is made up for their high damage and survivability in duels and fights, often forcing fights and hoping for long trades.
Tanks, on the other hand, have a lot of hard CC, with mobility that is used for initiation, and crazy ton peels and shields for helping targets. They are team fight oriented, helping others secure kills with their lockdowns, but cannot fight independently unless built for it.
So don’t expect a juggernaut to help save you with a shield or heal that they don’t have. And don’t expect a tank to bust through other enemy defences like a damage dealer.