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Module 4 of 6 - Stage 3

Identify the Most Promising Solution

You have a room full of ideas and limited time. Stage 3 is the funnel - a three-step process that moves from a large pool of possibilities to the one solution worth developing. Speed and objectivity are everything here.

THE SELECTION FUNNEL ALL IDEAS FROM STAGE 2 many ideas, unknown quality Screen MEETS REQUIREMENTS eliminated: can't meet requirements Rank TOP CANDIDATES qualitative - usually 3–6 ideas Score ONE SOLUTION carry to Stage 4

By the end of this module you will be able to

Describe the goals of Stage 3 and the screening-ranking-scoring funnel
Explain the difference between requirements and evaluation criteria
Describe four ranking techniques and when to use each
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Why Stage 3 needs to be fast and objective

At the start of Stage 3, you have a large pool of ideas from Stage 2. Some are strong, some are weak, and - critically - you don't yet know which is which. Your job is to quickly and objectively narrow down to the single best idea to develop in Stage 4.

The funnel has three steps: screening, ranking, and scoring. Each step uses different tools and different levels of effort, moving from quick and rough to thorough and quantitative.

Step 1 - Screening

Compare every idea against the requirements from Stage 1. Requirements are the "must-have" thresholds - if a solution can't meet them, it can't be implemented, no matter how good it looks in other ways.

Any idea that fails requirements is removed from the pool. Before discarding an idea, always check whether it can be modified to meet requirements - sometimes a small change makes a previously disqualified idea viable.

Screening is fast. The goal is just to remove the non-starters before spending time on anything else.

Step 2 - Ranking

From the ideas that survive screening, use evaluation criteria to qualitatively rank them from strongest to weakest. Evaluation criteria are measures that distinguish better from worse performance in stakeholders' eyes. Price might be both a requirement (must be under X) and an evaluation criterion (lower is better, even within the requirement).

Ranking is quick - you're not doing detailed analysis. You're just getting a rough sense of which ideas have the most potential so you can identify a small subset (typically 3 to 6) to carry forward for detailed analysis.

Four techniques for ranking - listed from fastest to most rigorous:

Individual voting
Fastest
Each person gets a set number of votes to distribute across concepts. Done independently to prevent groupthink. Totals are compared and the team decides which ideas to carry forward.
Borda Count
Fast
Each person ranks their top N concepts and assigns points by position (e.g. 4 points for first, 3 for second). Point totals are summed across the team. Good for forcing explicit prioritisation.
Pairwise comparison
Thorough
Every concept is compared against every other head-to-head. Win = 1 point, tie = 0.5 points each. Totals determine ranking. More thorough but more time-consuming.
Criterion-based ranking
Most thorough
Assess each concept's performance on each evaluation criterion separately, then combine. Most involved but most comprehensive.
Choosing a technique: quicker techniques (individual voting, Borda Count) are at the top of this list. More robust techniques (pairwise, criterion-based) are at the bottom. Match your choice to your available time. If you want high confidence, use more than one technique and check for consistency - agreement across methods is reassuring, disagreement is a signal to look more closely before committing.

Step 3 - Scoring

Take the small set of top-ranked ideas and analyse them in detail. Build simple prototypes, run calculations, test specific assumptions. The goal is to quantify relative performance and identify the single best idea to carry into Stage 4.

Expect surprises. The idea that ranked highest qualitatively may not score highest once you look closely. New information changes things. That's the point - scoring gives you real data, not intuition.

Iteration still applies

Even after you've selected a solution, you may need to go back. Specifications can change. A selected solution can turn out to be non-viable under deeper analysis. A new idea can surface in Stage 4 that's worth revisiting. Keep records of all ideas and the reasoning behind decisions - you may need them.