Co-owner Flavio Briatore has once again come under fire after Paul Hart quit less than a month after taking the job but Ephraim says the players must hold their hands up.
"It's crazy. If you keep changing you lose focus of where you want to go," he told the Kilburn Times.
"Different managers play different styles and maybe sometimes it gets lost in translation but at the end of the day the buck stops with us. I don't think so many managers in two and a half years could all have been wrong.
"We've got to be brave and admit we've not been good enough for a lot of that time. If you're winning games and you're in the top five or six in the league, I can't see the manager being changed. We're paid good money to work hard and we've all got to up our game."