Warning: My quick knead left me with a solid bread brick

I attempted to bake sourdough last Sunday and got impatient during kneading. I thought if the dough felt okay, it would rise fine in the oven. That was a huge error. The loaf came out heavy and dense, with a crust you could barely cut. Inside, it was gummy and undercooked, a total mess. I learned that proper kneading is non-negotiable for good bread. Now I always do the windowpane test before moving on, no shortcuts. Has a similar haste ever ruined your baking project?