(from Jeff Sauro’s 12/10/13 post on measuringu.com, link here.)
A 2009 study by Bob Bailey and researchers concluded that if a user’s first click was on the optimal path of the website, 87% would ultimately succeed
If the first click wasn’t on the optimal path, only 46% succeed
Jeff looked at 8 newer studies with data from 1000+ users and concluded that users of these sites were 6 times more like to succeed if their first choice was correct
Here’s Jeff’s table of results:
| Study # | Tree Description | Tasks | Average Success Rate | Average success from right path | Average success from wrong path | Number of primary levels | Average Ratio |
| 1 | Retail | 21 | 81% | 84% | 25% | 12 | 3.4 |
| 2 | Resort | 22 | 84% | 86% | 12% | 10 | 7.2 |
| 3 | Resort | 18 | 72% | 81% | 13% | 6 | 6.2 |
| 4 | Resort | 22 | 90% | 92% | 14% | 10 | 6.6 |
| 5 | Resort | 18 | 77% | 83% | 11% | 6 | 7.5 |
| 6 | Banking | 13 | 45% | 56% | 19% | 3 | 2.9 |
| 7 | Banking | 13 | 42% | 66% | 9% | 4 | 7.3 |
| 8 | Information | 10 | 82% | 88% | 11% | 7 | 8.0 |
| 80% | 14% | 6.1 |
Table 2: Eight tree test studies with average task success and average success rates for users who went down the optimal first path (80%) versus going down the non-optimal path (14%).
Jeff also realized that in this study, users were more successful if the primary navigation had more options (i.e. flat is better than deep). Jeff felt the data here wasn’t that deep but it’s an interesting observation begging for more research!
About Jeff Sauro: Jeff Sauro is the founding principal of MeasuringU, a company providing statistics and usability consulting to Fortune 1000 companies. He is the author of over 20 journal articles and 5 books on statistics and the user-experience. (from his post)
