The B2B buying process often involves a team (which includes executives, business managers, end users, technical reviewers, the CFO, procurement, etc.) rather than just an individual buyer. Each of those buying team members may have different evaluation and selection criteria that the vendor has to address. With ABM, teams can do so.
ABM also is more efficient. Some practitioners refer to it as fishing with a spear rather than a net from which you toss out the vast majority of the creatures dredged up. Early on, Sales and Marketing decide on the target accounts that they want to add or grow. Sales can be very helpful in then identifying the most important contacts and decision-makers. Helpful content created by Marketing is still valuable in educating the people at that company and creating interest, if not preference, for the vendor. With ABM, you direct the content toward those individuals rather than wait for them to find it.
ABM is explicitly outbound, not inbound.
There’s no comparison: a known database with known contacts wins every time.