Steven Gerrard is "well aware" of the job he signed up for and says "without a doubt" Rangers have improved.
The Ibrox side were knocked out of the Scottish Cup on Tuesday, losing to Aberdeen in a cup competition for the second time this season.
Gerrard's team are second in the Scottish Premiership - eight points behind defending champions Celtic.
"I've picked myself back up and I can guarantee you that I will improve personally moving forward," he said.
"I'm well aware of the job I signed up for. I know after a few bad results pundits and keyboard wizards will always be there. That's fine.
"There had to be a lot of change when I took over in the job. I knew I wasn't going to sort the problem out in one transfer window, not even two. But without a doubt we've moved forward, we've improved. Players that were here before have raised their game. Players that we've brought in, the majority, have stood up and done really well."
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Gerrard, who arrived at Ibrox after Rangers' second straight third-placed finish, signed 15 players last summer - 13 of whom are still with the club - and five more joined in January.
"We're doing everything we can to make Rangers a better team and a winning team," he said. "My confidence hasn't changed that I can make that happen but it's not going to happen overnight. This job was huge when I walked in and it was huge for a reason because a lot of things needed fixing.
"There will be change here, there'll be new players, there'll be better players because the current players need some help and support to keep growing and keep improving. We will get more quality and add to it. I don't expect the same in terms of numbers because I don't think we need a squad overhaul. I think we need some bits of magic, a couple of marquee players to add to what we've got to maybe go to another level."
'Tactics have to come second sometimes'
The former Liverpool and England captain, 38, says "it's been tough" since the midweek quarter-final replay defeat by the Dons.
Gerrard has injury doubts over midfielders Scott Arfield and Ryan Jack for Saturday's home league match against Kilmarnock, while defender Nikola Katic has been struggling with illness.
"There will be changes to the XI come the weekend," Gerrard added. "The worst thing as a footballer is to lose a game and to feel like you haven't done yourself or your supporters justice. It is interesting for me at the weekend to see what characters I have.
"I've not said much - sometimes you don't have to say much - the players know how the supporters and staff are feeling. It's about what you do on the pitch. If they have anything about them and they understand the club, it should be as straightforward as what they need to give going forward.
"Tactics and information have to come second sometimes, I am expecting a performance for the supporters as Tuesday was a tough one to take. The players have to think about what the supporters want to see."