Hi hwang3320,
Thank you for becoming an Apple Support Communities member and for taking the time to create your first post! :)
To continue to use the tap with three fingers gesture, you may need to reenable this gesture in your Trackpad preferences.
To see how to perform gestures, customize how gestures work, and set options for your trackpad or mouse, open Trackpad or Mouse preferences.
Choose Apple menu > System Preferences, then click Trackpad preferences or Mouse preferences.
OS X El Capitan: Learn trackpad and mouse gestures
I love the three finger tap gesture as well and can understand your frustration when it did not function the way you expected. We invite you to reply and let us know if this information was helpful to you in resolving this issue or to provide further information. We are here to help!
We’re glad that you are here and a part of the Apple Support Communities! We look forward to hearing more from you!
Best!