--- name: charter-decision-design description: 'Decision design for consequential choices involving uncertainty, competing preferences or shared commitments: integrate existing contributions, compare feasible options and recommend an actionable choice. Market bets are product strategy.' metadata: content_version: charter-decision-design@2026.10.16.0 --- # Charter ยท Decision Design A decision model connects choices to consequences and consequences to what the decision owner values. It is useful when that connection is obscure or contested. When a constraint, a dominant option or an agreed commitment already settles the choice, or an ordinary implementation merely has alternatives, the answer is that choice and the fact that settles it, in a sentence or two. A polished score table can be less informative than one well-explained trade-off. Whom a product serves and which market bet comes first are `charter-product-strategy`'s questions, and which machinery to build on is `charter-architecture-simplification`'s. ## Begin with what the participants have already contributed A shared decision rarely begins with an empty page. A partner's proposal, a previously rejected option, the user's correction and an expert's estimate may already settle much of it. Recover the meaning of those contributions before asking their authors to supply them again. Attribute a claim to its source; agreement about a problem does not imply agreement with its proposed remedy. Integration is more than summarizing each participant in turn. Put comparable claims against the same consequence and conditions. Two proposals may disagree only because one assumes an existing capability and the other assumes it must be built. Conversely, apparently compatible proposals may assign the same responsibility to different people. Separate common ground, factual uncertainty, preference differences and commitments that nobody has yet accepted. Disagreement has a mechanism. Participants may observe different facts, expect different causes, weigh the same consequences differently or disagree about who must act, and each difference is settled by something else. A choice can also commit several parties, each able to accept only its own consequence. When either happens, the [shared-decision reference](references/contributions-and-decision-rights.md) maps the kinds of disagreement, separates the parties' permissions and finds the smallest question that still needs an answer. ## Feasibility and value answer different questions A constraint removes an option from consideration; a preference changes its attractiveness. Treating an unacceptable exposure as a low score allows enough cost savings elsewhere to compensate for it. Conversely, treating a preference as a veto hides a trade-off the owner might willingly make. Options need to be feasible and materially different. Status quo, delay and a staged commitment are real alternatives only when their consequences are credible. A fictional "do nothing" that ignores an expiring contract biases the comparison as surely as a fictional perfect replacement. Dominance is a strong simplifier when one option is no worse on every material concern and better on at least one. Most consequential choices are not dominated: they exchange cost, speed, reliability, flexibility or downside. A model must show that exchange rather than conceal it inside labels. [Framing and alternatives](references/decision-workflow.md) explains how the decision boundary and horizon change what is actually being compared. ## A number is only as meaningful as its scale "Quality," "accuracy" and "error reduction" may count the same benefit three times. A weight on an undefined criterion means little; a swing weight values a specified improvement over a specified range. Changing the range changes the trade-off. Ordinal ranks express order, not equal gaps in value. Weighted sums assume that gains on one criterion can compensate for losses on another. Expected value assumes meaningful probabilities and comparable payoffs. Risk aversion, survival constraints and tail losses can make utility or robustness more relevant than the average. These are different models of the decision, not increasingly sophisticated versions of one score. The [quantitative reference](references/quantitative-methods.md) supplies dominance, swing weights, expected value, break-even probability, regret and value-of-information methods with their assumptions. Use the model whose assumptions fit the trade-off; numbers cannot supply missing preferences or make weak estimates objective. ## The switching boundary is often the real result A recommendation becomes intelligible when the owner knows what would make another option win. A cheaper system may win above a certain workload; a faster launch may win only if delay destroys enough revenue. Solving that boundary can be more useful than estimating every input precisely. Compute the boundary rather than asserting it: recompute both options just past the stated value and confirm that the ranking actually flips. A variable that can only widen the favored option's lead has no switching point. Say that the choice is robust to it, and look for the premise that can reverse it. Scenarios describe coherent possible states. Their count is not a probability, and coupled drivers cannot be varied independently without inventing impossible worlds. A robust choice remains acceptable over credible states; a fragile choice depends on a narrow premise. The latter can justify learning or staged exposure, but not automatically more analysis. Information is valuable through the better choice it enables, less cost, delay and exposure. If all possible findings leave the same action preferred, further research has no decision value for this choice. An experiment may still have another purpose, but should not receive credit for a choice it cannot change. Reversibility changes both downside and learning. Canceling a contract may leave migration work, expectations, team skills and integration residue. A pilot preserves an option only if those commitments stay limited and its observation addresses the uncertainty that matters. [Commitment and learning](references/reversibility-and-learning.md) develops these temporal trade-offs. The recommendation should expose the decisive rationale, the downside it accepts, the strongest countercase and the switching condition, which makes it actionable now and recomputable when premises change. When contributions or sources the decision rests on contradict each other on a point that changes the choice, first check whether they describe the same object, scope and time: an earlier decision still binds within its scope until its owner revisits it, while an earlier measurement merely ages. A corrected premise also changes the conclusions built on it, not only the sentence that stated it. An unstable external premise belongs to `charter-current-fact-research`.