People often make decisions based on what they think, not what they know. Operating experience has shown that some portion of the users of express lanes mistakenly choose the toll road over the free outer lanes because of the anticipation of sitting in congestion. On top of that, experts say 10-15% of drivers use express lanes out of habit, perceived increased safety, or the hope that travel times on the express lanes will be more reliable than on the general purpose lanes. None of these behaviors can be measured so they are excluded from the traffic models used for financing purposes. Due to the added traffic stemming from these “human errors,” toll prices dynamically rise to manage demand. The result is higher operating revenues than models predict, for some amount of time.