Sherwood oversaw the club's escape from relegation last season after taking over the struggling Barclays Premier League side in February.
But despite that survival, and surprise run to the FA Cup final, it remained an uncomfortable experience.
Villa lost their last two league games - including a 6-1 thrashing by Southampton - and finished just one place above the drop zone in 17th.
Former Tottenham boss Sherwood, preparing for his first full season as a manager, said: "I said in the latter stages of last season that there is, unfortunately, a losing mentality in the dressing room at Aston Villa.
"It is something we need to get rid of
It would help by bringing in new players who are used to winning and, also, it is for my staff to instil into them that it is a clean sheet
Everyone is on a level playing field and we need to move forward.
"It needs to hurt the players as much as it hurts me to lose football matches."
Villa have added to their squad this summer by signing defender Micah Richards on a free transfer from Manchester City and Sherwood believes the Premier League and FA Cup winner brings the champion spirit he wants.
Speaking at a special event in the Villa Park tunnel to launch the club's new strips for the 2015-16 season, Sherwood said: "He is a winner
He is a Premier League champion at a great age and is hungry for success.
"What he brings more than anything is a winning mentality."
Source : PA
Source: PA