Why winning streaks end... Lessons from Toyota.
Winners become sinners when confidence turns into complacency and arrogance. They over-estimate their own invincibility and under-value mundane disciplines. Whenever someone feels on top over a long period of time, they are tempted to neglect the very fundamentals that helped them succeed in the first place. They might even start to feel that the rules don't apply to them. Success means that people or teams or organizations survive long enough to need maintenance, repairs, and reinvestment.

Winners undergo natural aging processes, as people get older, slow down, leave. Facilities, tools, and bags of tricks get older, deteriorate, and run down. Newcomers might get less rigorous training while long-timers forget what they learned. As momentum runs down, people and buildings begin to look run down. Neglect takes on tangible physical manifestations, such as out-of-shape bodies or broken windows. Add to this the pressures in a recession to cut costs and defer expenditures.