Steve Borthwick says England "weren't good at anything" when he took over from Eddie Jones as head coach.
Borthwick was appointed in December after Jones' sacking, the culmination of a poor 2022 in which England won just five of 12 Tests.
On Saturday, they started the Borthwick era with a 29-23 defeat by Scotland in their Six Nations opener.
"I've been frank from day one in saying there's a lot of work to do," said the former Leicester head coach.
"When I looked at the team in the autumn, when I measured the team and got all the data for the team, we weren't good at anything. It was as frank as that.
"So we are trying to build some strengths in this team and some bits we are pleased about and some bits we are disappointed about. My job is to make sure we get some improvements for Italy."
Borthwick had spent just 11 days in camp with his players prior to getting their Six Nations under way at Twickenham on Saturday with a third successive Calcutta Cup defeat.
After the match, the new head coach said his team have "to go through some pain" in order to grow, but later praised his charges for their "magnificent response" after conceding points against Scotland.
England will host Italy as strong favourites in their next game on Sunday.
"There are multiple areas we have tried to change. You saw some improvement in the scrum against Scotland which I was pleased about because it has been ranked as the worst scrum in tier-one rugby," said Borthwick.
"We saw some improvements in the attack and speed of ball and we tried to improve the breakdown where England were ranked the ninth quickest, so one of the slowest in tier one.
"I'd seen a habit within the team of conceding points early and not being able to respond to it. We conceded points against Scotland and the biggest thing I was looking at was the response. I thought the response was magnificent."
He added: "I feel disappointed with the result. I asked the players to do some things differently. I have asked the players to play a new way.
"I have got to get the players to believe in themselves and get the players to bring their strengths to the pitch.
"I want them to play to the best of themselves, which we haven't seen them do for a while. I think you saw an improvement in that regard against Scotland."