it's possible that some ignition component failed.. perhaps a condenser or the ignition coil..
But this is very unlikely to happen compared to a wire being disconnected or broken or a switch going haywire. If the kill switch or ignition switch or their wires are malfunctioning, you may not get any spark.
There are just too many possibilities.. points.. flywheel.. lots of things.. can't get more specific without some clues. Something happened .. and something caused that something to happen.
what year is the bike.. NA50 Express? Urban Express?