There's a quiet moment every spreadsheet user knows: the number looks right, the math checks out, and then Power Query hands you 0.24 when you were expecting 0.25. The confusion is understandable, but the real issue isn't rounding. It's the gap between what we see and what the machine actually holds. When that user's cell displays 0.49, the underlying value might be 0.485 or 0.4849999, and dividing by 2 gives you something that looks like 0.245 but isn't quite there. Power Query isn't being stubborn. It's being honest about the binary floating-point reality that sits beneath every decimal you've ever trusted.
For the person asking "why is this?", the practical takeaway is straightforward: never assume the displayed value is the stored value. In Excel, what you see is often a rounded version of a longer, messier number. When you move into Power Query, you're working with the raw data, not the formatted label. That's why rounding to two decimal places can produce a result that feels wrong, even when the logic is correct. The fix isn't to fight the tool. It's to get comfortable with functions like `Number.Round` or to explicitly round earlier in the process, at the source, so the precision you intend is the precision you carry forward.
This isn't a flaw unique to Power Query, and it's not a reason to abandon the tool. It's a reminder that spreadsheets are not calculators with infinite memory. They're computational environments with constraints, and those constraints show up precisely when you push them. The user's instinct to ask "why" is the right one. That curiosity is what turns frustration into understanding. And understanding, in this case, means learning to check the true value before you judge the output. Use `Value.FromText` or inspect the raw data in the Power Query editor. You'll often find the culprit is not the rounding logic, but the number you didn't see.
So here's the concrete move: when a rounding result surprises you, don't assume the tool is broken. Assume the data is hiding something. Add a step to show more decimal places, or use `Number.Round` with an explicit precision to force the outcome you expect. The more you treat displayed values as suggestions rather than facts, the fewer surprises you'll meet. Power Query isn't out to trick you. It's just waiting for you to ask the right question.