The progress made by Alfa Romeo in 2023 was "steady" but simply "not enough", according to Valtteri Bottas.
Bottas scored just 10 points and finished 15th in the standings for his worst showing since his 2013 rookie season throughout the year as Alfa Romeo took ninth in the Constructors'.
Unlike other teams, the Hinwil-based squad which will revert to the Sauber name for 2024 and 2025 after the Alfa Romeo title sponsorship ended, could not make sizeable progress throughout the year.
The likes of Aston Martin, McLaren and Williams all made giant steps forward, and while Bottas also had more than his fair share of bad luck, the Finn feels the team was simply left behind in the development race - despite healthy progress.
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Thinking out of the box
"We have brought upgrades pretty consistently all through the year, and like any other team, there have been decent steps," Bottas told media including RacingNews365.
"Some have been really minor, so we haven't found anything big throughout the season, it has been steady progress but that is not enough.
"Other teams have found big steps, new concepts, innovative things, some might be copying other teams, but still we just did steady progress, but in this sport, that is not enough.
"Ultimately, the biggest thing is how the car was born.
"It was born better than last year's car, but not better enough. That's just how it goes, so there is not one thing that it is lacking.
"That is why I am really pleased that we are trying to think outside the box, and work with the new people that we have and that will be coming on-board."