I'd say it was too expensive to be used, otherwise they'd be used more often. Also one of them did not explode as intended due to the primitive detonation mecha

I'd say it was too expensive to be used, otherwise they'd be used more often. Also one of them did not explode as intended due to the primitive detonation mechanism, so there was some technical difficulties involved (at a time when they barely started using matchlocks, not even the more advanced and successful flintlocks). It was basically the equivalent of a boat filled with TNT as I understand, not that powerful. Could've been very useful at wiping out ports, cities and fleets, at the time, I doubt they had any qualms about it :-). Also, not that much of a war deterrent, as history can attest, lol...