Why are all measurements uncertain?

All measurements are uncertain because they are subject to various sources of error, including limitations in the measuring instruments, environmental factors, and the inherent variability in the phenomena being measured. Even the most precise instruments have a margin of error, which can be influenced by calibration, resolution, and the observer's technique. Additionally, the process of measurement often involves approximations and assumptions that can introduce further uncertainty. Therefore, recognizing and quantifying this uncertainty is essential in scientific and practical applications.