Signature based antivirus, as in "after the fact"-heuristics, remains the most useful. Because, as advanced as the other methods may be, their usefulness remain

Signature based antivirus, as in "after the fact"-heuristics, remains the most useful. Because, as advanced as the other methods may be, their usefulness remains limited by their public existence. Any malware writer checks their creations against VirusTotal and change it as long as anything flags.