In-depth Interview

Semi-structured one-on-one conversation to understand user motivations, pain points, and decision-making. Produces qualitative insight grounded in user voice, not stakeholder assumptions.

Process

Key Fields

Question it answers	Why do users behave this way? What drives their choices?
Participants & timing	5-8 per segment · 1-2 weeks
AI compatibility	AI helps with transcript synthesis and theme extraction; interviews must be conducted by a human.
Output	Insight report with themes, supporting quotes, and recommendations

Use when

Motivations and beliefs drive the behavior
Topic is sensitive or complex
You need to understand the why behind observed behavior
Survey data is flat or contradictory

Skip when

You need statistical significance
Quick quantitative validation is the goal
Budget allows only one research pass — use a broader method

Common Mistakes

Leading questions

"Don't you think X is confusing?" gets agreement, not truth. Ground every question in past behavior: "Tell me about the last time you..."

Stopping at five interviews

Empirical saturation research (Guest 2006, Hennink 2017) puts code saturation at 9-12 interviews. Five catches headlines, not patterns.

Skipping the pilot

One internal pilot session catches unclear questions and pacing problems before real participants.