Butter leaking from laminated pastry during baking is a common challenge that affects both rise and texture. When butter escapes, it leaves behind a drier, more cake-like pastry rather than crisp, flaky layers. This happens when butter isn't cold enough going into the oven, when dough is rolled too thin, or when there are tears in the dough layers. To minimize butter loss, ensure pastry is very cold before baking - even frozen. Use high initial oven temperature to set the layers quickly before butter can escape. Don't roll pastry too thin, as this can compromise layer integrity. Despite best efforts, some butter loss is normal, but excessive leaking indicates technique needs adjustment.