User blog comment:The Milkman/End of the Line/@comment-899316-20120703133109/@comment-1221773-20120704013346

We don't know how much time the events of ME3 span, but the impression I got is that it took more than a month to build the Crucible. However long it takes to build, though, making and using the first one required the combined resources of nearly every civilization in the galaxy, almost exhausted the galactic economy, and crippled the mass relays and Citadel. Another Crucible simply isn't a practical, go-to solution to deal with any future synthetic threats unless they're on par with the Reapers.

But the galaxy could always develop alternative means to battle synthetics. The Cerberus Arc Projector and Arc Pistol are examples of specialized anti-synthetic weaponry, and maybe we'll see more exotic technology arise as time passes.