nws tiller?
Four scenarios spring to mind:
1. The tiller push-button was malfunctioning and the nosewheel did not respond due to incorrect imputs from the tiller (maybe the tiller thought it was disconnected because of an incorrect signal) -technical-
2. The tiller push-button was unintentionally depressed in the heat of the moment. -human-
3. Maybe the turn was made with too much speed and a slight distraction caused a lack a monitoring of the groundspeed and the nose wheels started skidding even though the tiller was turned. Speeds greater than 10 kts are too great for 90-180° turns (especially when wet). Even on a dry runway this causes slight skidding. -human-
4. What SAASFO says. -human-
It happens to the best and will happen again, maybe to you, maybe to me. Seeking blame doesn't assist in the matter, finding out why it happened will help us to avoid making the same mistake. Obviously there'll be consequences, but that's a different matter. Happy taxiing.