They don't, but if I interpreted the post above correctly analog QCs aremuch easier to build
At least as far as I'm aware by digital they probably mean a generally programmable QC, whereas another approach is to encode a specific class of problems in the physical structure of an analog QC so that it solves those problems much faster than classical. This latter approach is less general (so for instance you won't use it to factor primes) but much more attainable. I think D-wave or someone like that already had commercial application for optimization problems (either traveling salesman or something to do with port organization)
At least as far as I'm aware by digital they probably mean a generally programmable QC, whereas another approach is to encode a specific class of problems in the physical structure of an analog QC so that it solves those problems much faster than classical. This latter approach is less general (so for instance you won't use it to factor primes) but much more attainable. I think D-wave or someone like that already had commercial application for optimization problems (either traveling salesman or something to do with port organization)