By designing their own chips and partnering with a foundry to manufacture them, Apple can create customized solutions that meet their product's specific requirements, distinguishing themselves from other PC manufacturers that use Intel/AMD chips.
Amazon recognizing it as an opportunity to stand out from the competition in the cloud services market by offering its own chips.
Tbf, Apple transitioned to Samsung by the early 2010s for their SoCs. The MacBook on Apple Silicon was a recent transition after the kinks in the iPad Pro (which is laptop specced) were ironed out.
> Amazon recognizing it as an opportunity to stand out from the competition in the cloud services market by offering its own chips
Exactly, and evangelizing earlier than other cloud providers.