F1 has become so used to Mercedes paving the way at the head of the field but that has all changed this season with Max Verstappen and Red Bull at the top of both the Drivers' and Constructors' Standings.
Some of the most dramatic moments of the season have come during the pit stop phase of the race. Whilst most races have become one-stop affairs, the intensity of the fight between Mercedes and Red Bull has prompted some two-stop strategies which has added to the excitement.
However, it's these key pit stop phases which have proved costly for Mercedes in recent races as they trail Red Bull by 37 points in the Constructors' Championship.
Monaco GP 2021 - Gasly gets in the way
Hamilton had a poor qualifying at Monaco on a track where your Saturday dictates the way your Sunday goes. However, Mercedes had a chance to strategically move Hamilton way up the order.
Instead, it went the other way. Mercedes opted to try and undercut AlphaTauri's Pierre Gasly but it did not quite pay off.
Gasly managed to stay ahead and his slow outlaps held Hamilton up as Sebastian Vettel and Sergio Perez went long to execute the overcut strategy.
Having started seventh, and despite two cars ahead of Hamilton failing to finish and start the race, the defending world champion failed to improve his position although he did pick up the extra point for the fastest lap of the Monaco GP.
Azerbaijan GP 2021 - Overcut once again
Hamilton turned things around in Baku during qualifying when things were looking rather ominous for Mercedes. He started from the front row of the grid and took the lead from Charles Leclerc.
Whilst Red Bull perhaps had a slight pace advantage, it felt like Hamilton had a good chance of the win with his excellent straight line speed.
Mercedes pitted Hamilton first and similarly to Monaco, it did not work. Verstappen set the fastest first and second sectors of the race to overcut Hamilton whilst Sergio Perez replicated the Dutchman's rapid outlap to jump Hamilton too, even though Perez's pit stop was not good.
We all know what happened with two laps to go when Hamilton made a mistake with the brake 'magic' button but the important thing here is, in terms of strategy Mercedes gifted a 1-2 to their main rivals from a leading position.
French GP 2021 - The biggest mistake yet?
Without doubt, Mercedes had a slight edge on race pace over Red Bull in Paul Ricard. Hamilton capitalised on a mistake from Verstappen at the start to lead the French GP.
However, for a second race running Mercedes handed the lead to Verstappen. Valtteri Bottas was forced to pit due to major vibrations on his W12.
This trigged an early round of pit stops which forced Verstappen to pit one lap later to cover Bottas. Hamilton had a 2.8 second lead over Verstappen to pit on the next lap.
When he emerged from the pit lane, he was neck and neck with Verstappen and he lost out. Mercedes underestimated the power of the undercut despite signs from Leclerc in the Ferrari who immediately set quickest sectors of the race on his outlap.
It was a surprise, but it was also an unnecessary risk from Mercedes. Other warnings such as the high tyre degradation from a track that was very wet in the morning, suggested that the overcut that worked in previous races was never going to work.
Things were not over yet though as Hamilton pushed Verstappen hard, forcing him into a pace that caused the Dutchman to make an unexpected second pit stop.
Mercedes were now stuck with their strategy to run to the end of the race with both drivers but ultimately Hamilton fell just one and a half laps short of the win.
France will hurt the most because Mercedes failed to win on a day where they had had a tenth or two in hand on Red Bull.
The Conclusion - What is wrong with Mercedes' strategy?
At a time when the margins are so tight, strategy and perfect pit stops have become race-deciding factors. Something that has changed within Mercedes' strategy team is that Rosie Wait, Mercedes' Head of Race Strategy, has been on maternity leave since the Spanish GP in May. Coincidence? Most likely.
James Vowles, Mercedes' chief strategist throughout the title winning years, remains the person who has the final say.
It's a role that will only come under more scrutiny if more mistakes are made by Mercedes. At times, Vowles and his team have judged things correctly such as the Spanish GP and the Bahrain GP when he relied on Hamilton's magical tyre skills to win the race.
But, even when Mercedes have had dominant cars, there have been occasions when they dropped the ball and it tends to be Red Bull who pick up the pieces.
More often than not, Red Bull nail their strategy and have incredibly fast pit stops so Mercedes are under huge pressure to match them in this department.
At the moment, that is not the case and it has cost Hamilton in particular a lot of valuable points. Mercedes have to turn things around and start to execute their strategies to perfection.
They have all the data in the world, and sometimes it's a simple case of reacting to a situation and the conditions rather than solely relying on numbers.