Vague vs Precise: Spot the Difference Ask someone to "make you a cup of tea." Done. They hand you a cup. But it is green tea, you wanted black. It is lukewarm. It has no sugar. And the cup is only half full. Nothing went "wrong" — they made you a cup of tea. But it is not what you wanted. Because what you asked for was vague. The Difference a Word Makes Here is the same request, written two ways: Vague version: > "Make me some tea." Precise version: > "Boil 300ml of water. Pour it into a mug. Add one PG Tips tea bag. Wait 3 minutes. Remove the tea bag. Add one spoon of sugar and 50ml of cold milk. Stir." The first version is a wish. The second version is a set of instructions. A person might be able to guess what you want. A computer cannot. Why Vague Instructions Fail When an instruction is vague, there are too many possible ways to carry it out. The person (or computer) doing it has to guess — and they will often guess wrong. Vague Instruction Problem Precise Version --- --- --- "Make the text bigger" Bigger by how much? Which text? "Set the title font size to 24 pixels" "Play some music" Which song? How loud? "Play the song Yellow by Coldplay at volume level 6" "Remind me later" When exactly is later? "Set a reminder for today at 5:30 PM" "Save the file" Where? What format? Overwrite or new version? "Save as Budget March2026.pdf in the Documents folder" "Turn up the heat" By how much? To what temperature? "Set the thermostat to 22 degrees Celsius" Every vague instruction on the left has dozens of possible interpretations. Every precise instruction on the right has exactly one. The Two Marks of a Precise Instruction 1. It specifies exactly what to do Not "make it better" — but what action, on which thing, to what degree. 2. It leaves no room for guessing There is only one correct way to carry it out. A recipe is a great example. A bad recipe says: "Add some flour until it looks right." A good recipe says: "Add 200 grams of plain flour and mix until no dry patches remain." A bad recipe is fine if you already know how to bake. A computer never already knows — it only knows what you tell it. The Goldilocks Problem Precision has a "just right" zone. Instructions can be: Too vague — not enough detail, too many interpretations Too wordy — so many words that the actual instruction gets buried Just right — exactly the detail needed, no more, no less You do not need to say: "Using your right hand, reach towards the green button, which is located in the middle of the left side of the remote, and press it firmly but not too hard until you hear a clicking sound and the volume indicator on the screen increases by one unit." That is too much. "Press Volume Up" is just right — assuming the person (or program) already knows what a remote is. The skill is in judging how much detail is needed for a particular audience and situation. Precision is a Habit Good programmers read their own instructions back and ask: Is there any word here that could mean two different things? Could someone follow this and end up with the wrong result? Am I missing any detail that is necessary to carry this out correctly? If the answer to any of those is yes — the instruction needs to be more precise. The good news: this is a skill, and it improves with practice. 🎯 Try This Yourself The Shape Description Game You need a partner, two sheets of paper and two pens. Sit back to back, or stand a book between you, so that neither of you can see the other's paper. 1. On your sheet, draw a simple picture using only squares, circles, triangles and straight lines. A house, a rocket, a robot face. Keep it to six shapes. 2. Now describe your drawing so your partner can copy it — but you are not allowed to say what it is . No "draw a house". Shapes, sizes and positions only. 3. Your partner draws exactly what they hear, and may not ask a single question. 4. Put the two drawings side by side. Laugh. 5. Round two: swap over, and this time you are allowed one extra tool — numbers. "A square 8 centimetres wide, in the middle of the page. A triangle sitting on top of it, the same width." What to watch for: round two will come out far closer, and the reason is the measurements. "Big", "near the top" and "a bit to the left" each have hundreds of meanings, and your partner has to pick one. Add a number and those hundreds collapse into one. 🤔 Check Yourself 1. Why is "turn up the heat" a poor instruction? Because it never says by how much , or up to what . One person nudges the thermostat by a degree, another pushes it to the top. Both followed the instruction. A precise version has a number in it: "Set the thermostat to 22 degrees Celsius." 2. Is more detail always better? No. That is the Goldilocks problem . An instruction can be so long that the actual action gets buried in the words. "Press Volume Up" is exactly right for anyone who has held a remote before. The skill is judging how much detail your reader — or your computer — actually needs. 3. You ask for "so…