But the rocks — which represented Mateo’s true priorities: preparing a key presentation, spending time with his family, exercising, and strategic planning — no longer fit. They sat on top of the sand and gravel, unstable and incomplete.

One weekend, his elderly mentor, Lucia, invited him to her garden. She placed a large empty glass jar on a table, along with a pile of big rocks, a bucket of gravel, and a container of fine sand.

“Mateo,” she said, “pretend this jar is your life.”

Mateo was a busy project manager in Madrid. Every morning, he opened his laptop to a flood of emails, urgent calls, and last-minute requests. He worked late, skipped meals, and still felt like he was falling behind.