Is it SpaceX philosophy or specifically Starship development philosophy? Because the development of the Falcon seemed to follow a pretty standard path. First they had three failures and two successes with the Falcon 1, and then they scaled up to Falcon 9, which worked on the first attempt.
The work towards booster landing and reuse was more iterative, but it was a special case. They had to be careful with the changes, because they were testing in production. The first priority was always delivering the payload. But once the booster had done its job, it was available for experiments.
Elon's spoken at length about the choice between design philosophies since the early days of Falcon. I'd submit that trashing Falcon 1 after the first successful flight to build Falcon 9 is an example of exactly that. Part of Falcon's success so early on was due to the choice of intentionally simple systems - a single pintle injector in the Merlin engine, RP1 propellant which is well understood, lots of relatively safe choices. And lots of work with the grasshopper test vehicles. But on flight 1 of Falcon 9 they flew Dragon. Flight 6 used hardware revision 1.1 and was the first to attempt a propulsive return. Flight 9 added landing legs. They made changes to basically every flight until Block 5 with flight 54.
Starship is the biggest rocket ever attempted, with uncommon propellant, most advanced engine cycle and it is designed to be fully reusable. Falcon was safe retreading of known ground comparatively.
The work towards booster landing and reuse was more iterative, but it was a special case. They had to be careful with the changes, because they were testing in production. The first priority was always delivering the payload. But once the booster had done its job, it was available for experiments.