A 55th minute goal from Reiss Nelson eased the Gunners into the FA Cup fourth round in a match that saw the home side outplayed for most of the first half.
Marcelo Bielsa's side showed just why they are top of the Championship table in a high tempo display of attacking verve in the opening period at the Emirates on Monday evening.
However, after words from Arteta during the interval, who was unimpressed with his side's performance in the opening 45 minutes, Arsenal stepped up a gear to ease past their visitors from West Yorkshire.
A good lesson
Speaking after the match Arteta admitted he was frustrated with his side's showing early on.
Improvement "has to be a process", he conceded, adding: "Tonight is a good lesson for us. [My team] can suffer in the first half or they can enjoy the second half. It is up to them.
"They way Leeds played made it very difficult for us. If you're not ready for it you will be exposed.
"When I see what I don't want to see and what I expect to see I cannot be happy and I have to let [my team] know."
Transfer business
Arteta was coy about any transfer business his side may undertake during the January window but insisted he wants and expects club captain Pierre-Emerick Aubameyang to stay with the north London giants.
Arsenal now face Bournemouth at the Vitality Stadium in the fourth round of the FA Cup on the weekend of January 25, with the Gunners travelling to Crystal Palace for a London derby on Saturday lunchtime as Premier League action resumes.
With Arsenal now tenth in the table, only nine points off fourth place, Arteta concluded by saying: 'We are building something.'
Bielsa on Lacazette's kick and VAR
Meanwhile, Leeds boss Bielsa refused to criticise Gunners striker and captain for the evening Gaetano Beradi after the Frenchman appeared to kick out at the Leeds number 28.
VAR did not deem the incident worthy of censure, with the Leeds boss adding: "I would never wish a red card for an opponent. I like to play 11 vs 11. It's better to believe nothing happened - which is what VAR said."
