He said a good Opposition was needed to "hold the Government to account".
People also voted for "continuity", he said, in an election dominated by Covid-19.
Although he held on to his Waimakariri electorate, Doocey's majority last election – 10,766 votes – was wiped away over the weekend, with him keeping his seat with a much slimmer 1976 majority.
National Party support in the electorate also dropped from 53.5 per cent in the 2017 election, to 28.7 per cent in 2020.
"Unfortunately I felt the effect of that."
Doocey arrived at parliament today and said it had been "a tough few days" and it was good to be back in Wellington.
He said he was humbled by the support he received in his Waimakariri electorate which returned him to Parliament.
National needed to have a culture where they don't have leaks and be unified, Doocey said.
"Because this job is about the people we serve in the country - it's not about us."
Labour was the big winner in greater Christchurch this election with nearly all of the seats going to the party.
Doocey and Nicola Grigg (Selwyn) are the only National candidates who won their electorate in the area.