Swansea's 3-1 defeat against Tottenham on Saturday has left them only three points clear of bottom-placed Cardiff City, with Williams admitting the team are at a loss to explain their slump.
He said: "If I could put my finger on the problem, I'd stop it. Listen, we're working hard. We have played against top-quality teams, but they're games we'd expect to get something from, so it's not an excuse.
"We've had injuries to key players, but that's not an excuse.
"We need to do better. There's not much more I can keep coming out here and saying to you. It's the same things."
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball