Sheikh Mohammed bin Rashid has criticised poor standards at a government service centre and pledged to remove staff who are not performing well.
The Prime Minister and Ruler of Dubai shared an image of lengthy queues at a branch of Emirates Post.
He spoke of the need for a broader focus on customer service and "transparency" in public services.
"I have received a photo from a secret shopper showing the level of services in Emirates Post," he wrote on Twitter on Monday.
"This is not our level. These are not our services.
"And whoever continues to provide such level of services will not be among my team."
He publicly shared a performance report that focused on how simple changes to working methods could bring big improvements.
"We dispatched a team to check the level of services in one of the centres in Emirates Post", he wrote.
"The team came back with this report. I present it to everyone to see with utmost transparency.
"And I say to everyone in the government: nothing will be overlooked but will be followed up with utmost transparency."
The report, which Sheikh Mohammed shared on social media, focused on the postal centre in Karama.
Inspectors found a "lack of service standards" and that "serving customers is taking too long".
They found 75 per cent of customers were simply there to pick up an emirates ID in person.
Staff would send text messages to "a large number customers and at the same time", rather than staggering them, and that about 3,000 people per day were coming through its doors.
It further found an inefficient system that meant customers were sent to multiple desks within the same office to complete the process.
"The centre’s employees need to build more performance and customer interaction skills", it concluded.
When The National visited Emirates Post in Karama on Monday, only three of the seven service counters had staff present, at the busiest part of the day, with 15 people waiting in line at one desk.
Some staff also appeared willing to serve customers who had jumped the queue.
Omar Mohammed, 26, from Pakistan, said the process in service centres is often drawn out and inefficient.
"Person to person transactions are still difficult across many services," he said.
"It is much easier to do your business online, if you can, because the standard of service from people on the other side of the counter is so inconsistent," he said, adding most retailers and government centres have improved.
“You used to have to rely on machines in shops, to pay your bills, and there was always some issue with them,” he said.
Another customer had already read Sheikh Mohammed's comments about Emirates Post.
"I am delighted to see that he is doing something about waiting times,” said the Indian worker, who was waiting for his Emirates ID card, and asked not to be named.
“It is really frustrating as I have been here for 40 minutes and I don’t know when I am going to be seen.
“I am used to it. When you are queuing for anything like this in Dubai you know there is going to be a long wait.”
Another customer was more fortunate, being seen in just 15 minutes.
“But it's always hassle when you have to collect any official documents or set anything up in Dubai," he said.
Social media users speculated as to which public service provider could be next in the push for efficiency, and some suggested local telecoms providers.
Hanna Mera, writing on The National's Facebook page, said: "This is your call, improve your service. Enough of waiting for two hours, standing ... payment issues."
Thomas Biesewig criticised broader postal delivery services, saying: "During my time in UAE only 50% of my mail has arrived and then with a delay of weeks or months. Christmas cards arrived a week before Easter."
Other users said offering more part time jobs - which are relatively rare due to the way the visa system works - would help the public and private sectors to better handle busy periods of the day.
Sheikh Mohammed has previously pledged to improve efficiency in public service.
Last year he criticised 'unacceptable' government employee survey results that found only 60 per cent of employees at five offices were satisfied at their workplace. He gave managers six months to improve morale and standards.
He also told staff at Dubai International Airport to "raise the bar" during a tour last summer.
And he famously toured Dubai's Land Department and the Department of Economic Development, finding empty desks on the morning that staff were due to return to work after a long weekend.