The Approximate distribution of the inherent causes of machinery failures in Industrial Plants.
70% to 90% of the failures –> latent design errors (usually systemic errors)
50% to 75% of the failures –> Operational errors
50% to 70% of the failures –> Maintenance errors
10% to 30% of the failures –> Abnormal environmental stress
1% to 5% of the failures –> Wear Out
Though these figures represent the distribution of causes of machinery failures, I suspect the same distribution holds true for any other system like Organizations.