The best power bank is useless if it doesn't have this feature

I own a good dozen portable power banks that I have acquired over the years. Shockingly, they all still work, even if the ones I bought a decade or more ago are slow to charge and have smaller than ideal battery capacities. Some have multiple ports; the newer ones add niceties like MagSafe capability, built-in screens to show charging status (and more), and other important features your next power bank needs to have. But almost all of them have one thing in common that I find crucial to a portable power bank: a built-in cable.