Where each mechanism comes from, how we grade the evidence, and what we do when the literature is still arguing. Nothing here is a trade secret: the method only works if it can be checked.
For a behaviour to happen, it takes capability (the person can), opportunity (the context allows it) and motivation (it is worth doing). If one fails, the behaviour does not occur — and the right intervention depends on which one failed.
That is why training someone who already knows changes nothing, and why recognition does not fix system friction. The diagnosis exists so you do not get the condition wrong.
They know they should, but lack knowledge, criteria or mental space. Six mechanisms: A1 to A6.
typical intervention: instruct, simplify, put criteria in writing
The tool, the routine or the group gets in the way. Two mechanisms: B7 and B8.
typical intervention: remove steps, change the channel, make the new practice visible
They can and could, but choose the usual way. Seven mechanisms: C9 to C15 — the largest sector, and that is true of the problem, not an accident of the design.
typical intervention: redesign incentive, authorship, reciprocity
each with the signal that gives it away and what tells it apart from its nearest neighbour
The grade does not measure how much we like the model: it measures the state of the literature. A D stays in the base because naming the phenomenon helps the conversation — as long as you know the ground.
Effect sustained by multiple independent studies and quantitative synthesis. Direction is reliable; magnitude varies with context.
Solid base in the field or the lab, without the density of replication of an A. Use it, and observe the result.
It exists, but its size and conditions are contested. Treat it as a hypothesis to test, never as the sole basis for a decision.
Popular, yet with a thin or methodologically contested empirical base. It serves as vocabulary, not as justification.
Much of the behavioural science popularised in the 2000s did not replicate well. Rather than removing those models from the base and pretending they never existed, we mark them C or D and explain what is in dispute.
When a new meta-analysis weakens an effect, the grade drops and the change enters the changelog with date and reason. You can see what the tool used to recommend and what changed.
A mechanism graded A can have low support in your case, and a C can be shouting in the signals. The grade is about the literature; support is about your session. The two rulers appear together, never summed.
Human curation: the base does not rewrite itself from usage. Every change to the taxonomy goes through review by whoever answers for the method — and stays public.
No author quote enters the tool without human verification of the source. Popular but disputed attributions are published without attribution or simply not used.