Not because your team is too slow. But because your QA sits in the same location as your developers.
Every Scrum Master knows the pattern: the last two days of a sprint belong to QA. Developers twiddle their thumbs or start new stories that are guaranteed not to finish. The result: carry-over. Sprint after sprint.
The usual response? Form a separate QA team that works "vertically" across multiple Scrum teams. That solves one problem—and creates three new ones.
Over recent years, I've repeatedly observed the same pattern across my projects. It became particularly evident when managing multinational teams for a company-wide data platform in automotive development—there the problem with vertical QA structures showed its full impact: The QA bottleneck at sprint-end isn't a capacity problem. It's a timezone problem.