The effect of delays on penalty conversion
For FiveThirtyEight, TruMedia's Albert Larcada analyzed how waiting time affects penalty conversion, revealing that longer delay appear to increase the likelihood of a miss.
"The success rate of penalties with a wait time of less than 150 seconds is 76 percent, while the success rate of penalties with a wait time of greater than 150 seconds is 73 percent. With the relatively large sample of penalties we have, the difference is statistically significant."
Full article: FiveThirtyEight (by Albert Larcada, Director of Analytics)