Williams is mum on the reasons why the build-up of its FW42 suffered delays, but deputy team principal Claire Williams has dismissed rumors of a supplier or budget issue.
The British team put its new car on track for pre-season testing two days after its rivals last week at the Circuit de Catalunya, forcing Williams to play catch-up during its testing programme.
While no clear reason has been given for the FW42's belated start, Claire Williams set the record straight with regard to speculation that emerged last week.
"I think there were many stories around about what potentially could have been the cause of it," she told the media in Barcelona on Wednesday.
"A couple that I read were that there were issues with external suppliers. That wasn't the case. Or that financially we were in a difficult position and that had an impact on car build. It didn't."
"I think we take for granted sometimes that we're going to get one car to the test track and two cars to the race track," she added.
"But Williams still builds, or designs and builds it race cars in-house, in their entirety.
"There are 22-odd-thousand parts to a car, which we have to design, which we have to manufacture, which we have to assemble, which we have to put through crash testing, etc…
"And that's an enormous job, and we just didn't make it for a number of reasons.
"I think it can happen, I think we've seen historically that it can happen, and we need to just make absolutely sure that the situation doesn't happen again."
Williams is conducting an internal investigation into its processes, the results of which likely won't be known for some time.
"There has been some work started, but it will probably take a few weeks to fully compile that, and we have to get it right because if we don't get the review right, then we're not going to get next year's programme right.
"So we've got to take our time and make sure we cover every base off, and make sure we get it right for next year."
Both George Russell and Robert Kubica have enjoyed relatively trouble-free sessions so far this week, at least demonstrating the FW42's reliability, if not its speed.
"I think we still have to wait and see exactly where we are," said Williams.
"Clearly we don't want to be at the back again, but I have always said, and I said last week, this is journey, it is a pathway and other teams have done an exceptional job to maybe make better inroads than we have.
"But we'll keep working hard to make sure that we recover from where we were last year, and from where we currently may be in testing."