What are the three types of stakeholder requirements that elicitation techniques aim to identify?

Conscious (can state it), unconscious (assumed/forgotten), and subconscious (can't yet articulate it) — no single technique surfaces all three.

1. Conscious requirements: Stakeholders know what they want and can articulate it
2. Unconscious requirements: Stakeholders have needs they're not actively aware of but would recognize if pointed out
3. Subconscious requirements: Deep needs stakeholders can't easily express - often discovered through observation or creativity techniques

Important: There is no universal method to elicit all these requirements. The choice of technique depends on:

• The type of requirements being elicited
• Time and budget constraints
• Stakeholder availability
• The RE's experience with the technique
• Project risks and opportunities

Go deeper:

• Requirements elicitation (Wikipedia) — the techniques used to surface stated and unstated stakeholder needs.