Why couldn't I get the clouds, shadows and details in the first picture?

Ello,,,,,, !

I took two pictures this morning, and I wonder why the first one didn't show the sun shadows, the clouds or neither the details. However, when I changed the setting to Aperture Priority, it DID capture all the details....?

Given that i'm still learning, and we're all still learning, any idea why that happened?

many thanks!

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I can can the can but the can can't can me!