How the airport taxi works
Taxis in Dubai are metered, regulated and generally fine. At the airport you join the rank outside arrivals, the flag fall is higher than a street pick-up, and the meter then counts distance and time. That last word is the one that matters: time. The same route costs one thing at 4 am and another thing behind an accident on Sheikh Zayed Road.
At peak arrival banks the queue itself is the hidden cost. Several wide-body flights land inside the same half hour, and the rank is sized for an average evening, not for that.
How the fixed transfer works
A private transfer inverts the deal: the price is agreed before the trip and printed on the booking. The chauffeur meets you inside arrivals with a name board, the office watches the flight number, and the free hour of waiting starts when you walk out into arrivals, not when the wheels touch down.
Traffic, the toll gates on the way, parking and the airport pick-up fee are the operator's problem, not yours. If the drive takes longer, the price does not move.
When the taxi is the right answer
Travelling alone with a cabin bag, landing at a quiet hour, going somewhere close: take the taxi. It is there, it is metered, and for a short hop the difference is small.
When the transfer wins
Three or more people, real luggage, a child seat, a late-night landing, a meeting you cannot be late for, or an Abu Dhabi leg: the fixed price usually beats the meter, and the certainty always does.
The honest summary: a taxi is a good product with a variable price. A transfer is the same drive with the variability removed. You are paying to delete the question mark.