Choosing between two important things
The short answer
If both are important, importance has stopped discriminating and you need a different question. Ask these five in order and stop at the first that gives an answer:
- Is either blocked? If so, the unblocked one goes first — and the blocked one's real task is the message that unblocks it.
- Does either have a real deadline? Not a preference. A date with a consequence.
- Does either unblock someone else? Work that is holding up another person is worth more than the same work in isolation.
- Is either reversible? Do the reversible one first; you can correct it cheaply if you were wrong.
- Which would you regret not having started? Last resort, and honest.
Most ties break at question one or three, which is why they come first.
Why "which is more important" fails here
Because you have already asked it and it returned a tie.
There is a formal version of this, and it is not a platitude: no ordering rule is optimal across objectives. Earliest-deadline-first is provably optimal for meeting deadlines; shortest-job-first is optimal for minimising average wait; neither dominates the other, because they optimise different things. When two items look equal, what has actually happened is that you have not said what you are optimising for today. The formal version.
The five questions above are not a ranking. They are a sequence of different objectives, ordered so the cheapest discriminator runs first.
What each question is really asking
Blocked or not is first because it costs thirty seconds and can save a morning. Committing your best hours to something that needs an answer from someone else is the most expensive scheduling mistake available, and it is entirely avoidable by asking.
Deadline is next because a date is the one property that makes an item genuinely non-negotiable. Be strict about what counts: a date somebody preferred is not a deadline. A date with a consequence is.
Unblocks someone else matters more than it feels like it should. Two hours of yours that frees a day of someone else's is a better use of two hours, and this is invisible unless you ask specifically — the person waiting usually has not told you.
Reversibility is the most underrated of the five. Between two things of equal weight, the one you can undo is the safer first move, because being wrong about it costs less. Irreversible decisions deserve the slot where you have the most information, which is later.
Regret is last because it is the least reliable, but it is honest, and by the time you reach it the two things genuinely are close — at which point the cost of choosing wrongly is small and the cost of continuing to deliberate is not.
The thing that actually goes wrong
Not choosing badly. Choosing neither.
A tie is comfortable to sit in, because while you are still deciding, neither thing has been given up. The deliberation feels like diligence and is usually avoidance — and it has a cost that nothing records: both items stay open, so both stay slow, and the day passes in the comparison rather than the work.
If the five questions do not break the tie in two minutes, the two things are close enough that the choice barely matters. Pick either and start. That is not resignation; it is the correct response to genuinely equal options, and it is almost always better than a third round of comparison.
And if they are both urgent and both important
Then the honest problem is not selection, it is capacity — and no ordering rule creates hours. Either something moves, or something is late, and the useful action is telling whoever is affected while it is early enough to matter. Sorting on both axes will tell you which; it will not tell you where the time comes from.
Where to go next
- Is there a best prioritisation method? — why the tie means the objective is unstated
- How to use the urgent/important matrix — separating the two axes properly
- How to prioritise your tasks — the three conditions
Using this in Decide One
Decide One's Ivy Lee mode makes you commit to an order and then holds you to it — the second line does not open until the first is closed. That removes exactly this deliberation from the middle of the day, which is where it is most expensive.
A line you did not finish is unfinished. It is not marked against you, and a day you did not open is not counted.
Open Decide One — free to use, with no account. Nothing you write leaves your device.
Decide One is a priority instrument. Bring the day into view, choose a method, give the first thing real time.