How much D&D prep actually gets used?

"I over-prepare" is one of those pieces of self-knowledge that never changes anything. It is too vague to act on. You cannot prep 30% less in general. You can only stop doing a specific thing, and until you know which thing, the advice is just guilt with extra steps.

So it is worth being precise. Prep is not one activity. It is six or seven different activities that happen to occur on the same evening, and they have completely different odds of ever reaching the table.

What reliably gets used

The opening scene

This is the only piece of prep with something close to a 100% hit rate, for a simple structural reason: you control the start of the session. The players decide everything after that, but nobody decides the first sixty seconds except you. A paragraph describing where everyone is and what is already going wrong will be used, every time, in every campaign you ever run.

It is also one of the cheapest things to write. If you only ever prep one thing, prep this.

Names

Not personalities, not backstories. Names. A list of twelve names you can read off when a player asks the barkeep what he is called. This gets used constantly, costs almost nothing, and prevents the single most common thing that breaks the spell at a table: the DM going "uhh… Bob?"

Encounters you were fairly sure about

Combat prep has a good hit rate because you usually build it for a fight that was already likely. If the party is walking into the bandit camp, the bandits will probably be there. The waste in combat prep is not the encounter itself, it is the three alternative encounters you built in case they went somewhere else.

What reliably gets wasted

Backstory and history

The classic. Pages of who ruled the kingdom four hundred years ago, prepared for a party who will never ask and would not listen if you told them unprompted. This is the most-written and least-used category in the hobby, and it is written because it is fun, not because it is needed, which is fine as long as you are honest that it is a hobby within a hobby rather than session prep.

Written-out dialogue

A speech survives roughly until the first player interrupts it, which is about nine seconds. What you actually need is what the NPC wants and what they will not say, one line each. From those two facts you can improvise any conversation. From a script you can only be derailed.

Anything past the third or fourth scene

Prep decays fast. Scene one is near-certain, scene two is likely, scene three is a guess and scene four is fiction. Prepping a whole session in linear order means the back half is written against a version of events that will not happen. This is why the "three to five scenes" rule shows up in every good prep guide. It is not laziness, it is where the returns stop.

Endings

The most seductive waste. You imagine how the arc resolves, write toward it, and then either the players do something better or you find yourself steering them toward your version. Prep situations and let the table produce the ending; it will be more surprising than yours and the players will own it.

Rough numbers, and why yours will differ

Here is the shape most DMs find, though the exact figures vary a great deal between tables.

Treat that as a starting hypothesis, not a result. A DM running a heavy intrigue campaign will use NPC prep at a far higher rate than one running a dungeon crawl, and both will be right about their own table. Your numbers are the only ones worth changing your habits over.

Work out your own numbers List what you prepped, tick what got used after the session, and see which category you waste. Free, no account. →

How to actually use this

Run the measurement for three sessions before you conclude anything. One night is noise. A session where the party ignored everything you built can be followed by one where they walked straight down the middle of it.

Then take your worst category and halve it. Not eliminate, halve. Run a session that way and see whether anybody notices. In almost every case nobody does, and you have bought back an hour of your week.

One important caveat

A low hit rate is not automatically a failure. Some prep is insurance: you write the guard captain because the party might go to the barracks, and the value was in being ready, not in being used. Cutting all of that would make you a more efficient DM and a more brittle one.

The distinction worth watching is between prep you were glad to have ready and prep you had forgotten you had written. The first kind is insurance. The second kind is just work.

The other half of the problem

Prep is the half of DM admin that people talk about. The other half is remembering what actually happened: the NPC you improvised four sessions ago whose name you have lost, the promise a player made that you were going to bring back.

That half is much harder to fix with discipline, because it is not a question of effort. You cannot decide to remember a detail you did not write down at the time.

Scrivorn Records your session and writes the recap, keeps your campaign wiki current, and gives your players a portal to read between games. →