The Hockenheim stewards sanctioned Rosberg after they deemed the Mercedes driver had forced Max Verstappen off track at the hairpin when overtaking the Red Bull.
Rosberg elected to serve his five-second time penalty at his third and final pit stop but his W07 was left unattended for over eight seconds.
“It was a stopwatch failure, the time thing failed,” Wolff explained. “It didn’t function like it should have. We could have also counted, one thousand and one, one thousand and two, one thousand and three but we relied on the stopwatch and it let us down.
“Even in a Formula One team with all the high-tech, if you get to take out the instruments that you usually don’t use like a stop watch, they can fail and the stop watch didn’t start properly and once we realised we had to take it safe and this is why it took longer than normal.”
Rosberg’s lenghty time penalty was just the latest hurdle in a tough afternoon for the German driver, who suffered a poor start from pole position and could not out pace the Red Bulls to finish second behind title rival Lewis Hamilton. Wolff says the events just snowballed for Rosberg at Hockenheim.
“You know on a day like today you are having a shitty start OK, you are losing two positions, you battle your way back and you are being penalised, instead of spending five seconds in the stands you are spending eight seconds in the stands.
“There is a human being in the car and on top of that the set up probably overheated the tyres. If you put that all together and you are having a bad day, that is the consequence.”