The Pole suffered his first non-finish of the year in Sochi, as he was pulled from the event shortly after teammate George Russell retired after hitting the wall with a car issue.
It marked Russell's second DNF of the season, the first of which came one weekend prior to Sochi, in Singapore.
After the race, senior race engineer Dave Robson said: "We took the opportunity behind the early safety car to pit Robert twice aiming to complete his race using only option tyres.
"Meanwhile we were able to leave George out and run long until a virtual safety car provided an opportunity for a cheap pitstop on to the qualifying tyre.
"Unfortunately, an issue shortly after the subsequent restart caused George to lock a front wheel, damaging the car further.
"We opted to retire Robert soon afterwards in order to conserve parts ahead of the intense flyaway races which end the season. It’s a very disappointing way to end two weeks on the road."
Kubica described his weekend as 'very disappointing' as he sets himself for the final five races of the season before he leaves Williams at the end of the year.
"This weekend has been very disappointing," he said. "You always have to try your best with what you have, and this is what I was trying to do.
"After George’s DNF, the team decided to stop my car, to take care of the parts that we have on the car. We are not in an easy situation and Japan is around the corner."
Bahrain International Circuit - Winter testing