The British squad have made significant progress in recent seasons, climbing from ninth in the constructors’ championship in 2013 to third in 2014. But despite picking up a number of podium finishes along the way - and retaining their third place in the standings this season - they have not recorded a race win since Pastor Maldonado’s surprise triumph in Spain in 2012.
It’s a fact that clearly rankles Symonds, who has had his sights set on adding to Williams' 114 Grand Prix victories since his arrival in mid-2013.
“I want to be winning - there is no point in doing anything else,” he told Formula1.com. “Where are we from winning? We are, in raw performance terms, about one percent off from where we need to be.
“Operationally we are still a little bit immature [too]. Mercedes have a pretty good team - not without mistakes as we have seen in Monaco - but under pressure mistakes can happen. We are not quite were I want us to be operation-wise.
“So all I want is over one percent more on raw performance - and a very slick operation.”
Williams, who use Mercedes power units, picked up their third podium of the season in Italy last weekend, though Felipe Massa finished over 45 seconds adrift of race winner Lewis Hamilton.
The team have only finished within 20 seconds of the lead car twice this season - in China (where Massa and team mate Valtteri Bottas came home 8.5s and 9.8s respectively behind Hamilton) and in Austria (where Massa took the flag 17.5s down on race winner Nico Rosberg).
The closest Williams have been to pole position in 2015 is 0.543s, which was Massa's deficit to Hamilton in qualifying at Monza.