Sky F1 pundit Karun Chandhok believes Williams was wrong not to have sealed a deal with Honda back in 2017 given how the Japanese manufacturer has helped Red Bull.
Sauber and Williams were rumored to have coveted Honda power for 2018, with the Swiss outfit signing a pre-agreement with the engine supplier before backtracking and switching its allegiance to Ferrari.
However, Williams never pursued a deal with Honda, preferring to remain loyal to Mercedes and its supply of reliable engine.
Chandhok says that decision was perhaps another misstep by the Grove-based outfit.
"It is interesting how many articles I’ve seen online in recent weeks about various things Williams could have done differently," said the former F1 driver, speaking in a Sky F1 Vodcast.
"From not letting Adrian Newey go to the BMW relationship breaking down, things like that… But those are all long gone and there are two critical points in recent times.
"Obviously the alignment with one of the major teams and the other is the Honda deal."
Chandhok believes Honda would have provided Williams with technical and financial benefits, the likes of which were well exploited by Red Bull Racing last year following its switch from Renault to Honda power, with Max Verstappen securing three wins during the 2019 season.
"I think that when they sit back - and they would probably never say this publicly - but when they talk about what they could have done, for me, I think the Honda deal is the one that was something they should have chased more actively," added Chandhok.
"Look at how well it has turned out for Red Bull.
"We all thought Honda would come good at some time. You need to work with them, it is a different culture, it didn’t work with McLaren but Red Bull has managed to unlock their potential.
"I know hindsight is 20/20 but you do really wonder if a Williams-Honda combination could have done exactly what they are doing with Red Bull.
"Financially Honda would have invested money into the programme and built that up."