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Cavendish finished 29th after his Great Britain team-mates failed to reel in a late breakaway in the 250km race that finished on The Mall.
"The British team were a victim of their own success. The same tactics worked at the World Championships [where Cavendish won gold]. Then, in the Tour de France, Cavendish battered them on the Champs Elysees in Paris. There were eight riders helping in Copenhagen, just four today. While four people can influence a race, they cannot control it. The problem is nobody wanted to ride against Cavendish on the Mall because they knew they would come second. The team did everything they could, other riders did not contribute to the race and they missed out too. Andre Greipel is the second best sprinter in the world but he and his German team sat back."
Vinokourov sprinted clear of Colombia's Rigoberto Uran in the final stages of an eventful race.
Norway's Alexander Kristoff pipped the rest of the breakaway pack to bronze.
Cavendish, who finished near the front of the main peloton, refused to blame his team-mates, who included 2012 Tour de France champion Bradley Wiggins and runner-up Chris Froome.
"We rode the exact race we wanted to ride," Cavendish told BBC Radio 5 live. "We controlled it with four guys for 250km and we couldn't do any more. We are human beings.
"There was a group of 22 who got away and we couldn't pull them back. The four guys who ran all day couldn't do it.
"I can be proud of how the lads rode today. I'm proud of my country because there was incredible support. The guys are sat there, they are spent. They have got nothing left in the tank. It's incredible to see what they gave for the cause."
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Team GB's race strategy was simple: get Cavendish to Buckingham Palace within striking distance and let the Manx Missile demonstrate his finishing prowess.
It was a plan that worked beautifully at the World Championships in Copenhagen last year.
But there were two flaws with the plan: one, everybody else knew it; and two, this time the 27-year-old Brit only had four support riders to pace him to the end, not seven.
What gave Cavendish - and the millions of British fans watching on the course and at home - so much hope, however, was the fact that this team was undoubtedly the best Britain had fielded at an Olympic road race.
With Tour de France champion Bradley Wiggins, Tour runner-up Chris Froome, seasoned campaigner David Millar and national champion Ian Stannard riding for the world champion, Cavendish's claims that this was a "dream team" were not unfounded.
Yet it was not enough. With almost every other nation in the race desperate to avoid a sprint, Team GB were always going to struggle to keep the 144-strong field together.
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A pattern was set from start of the race when, after the riders had avoided an errant dog, 12 men from as many countries jumped clear to form the first breakaway.
Among this group were dangerous riders such as Australian veteran Stuart O'Grady, Slovenian star Janez Brajkovic and versatile Dutchman Lieuwe Westra - and they soon built their lead to six minutes.
But with half the 250km distance completed, Team GB seemed comfortable at the front of the chasing group.
It was at this point that the nature of the race changed ever so subtly, but ever so significantly.
First, Italy's Vincenzo Nibali broke away, dragging two Belgians and a Dutchman with him. The threat to Cavendish did not seem obvious, because the time gaps looked manageable, but the danger grew  as more riders infiltrated this group.
With the final lap of Box Hill completed, Cavendish looked fresh. A fast and flat 30-mile dash back to London lay ahead of him and expectation of a first British gold medal at London 2012 grew.
But the lead group was now 30-strong, the original dozen and Nibali's chasers, and when Belgian one-day specialist Philippe Gilbert sprang clear, panic set in.
Gilbert had gone too early, but Fabian Cancellara, a silver medallist in this event from Beijing, was far too strong a rider to be two minutes clear with 20 miles to go.
But the Swiss star made a critical mistake on a corner coming out of Richmond Park and his race was done. By this stage, so was Froome's and it suddenly became clear that there would be no grandstand finish for Cavendish and Team GB.
The remaining leaders now started to eye each other and it was Vinokourov, who completed a two-year drugs ban in 2009, and Uran who grabbed the initiative with a smart burst through Putney.
The last five minutes of the race were an anti-climax for most of the spectators but a masterclass in racing from "Vino".
Uran, a team-mate of Cavendish at Sky, was completely outfoxed by the Kazakh in the sprint and had to settle for silver.
Mark Cavendish's Olympic gold medal bid ended in disappointment as Alexandre Vinokourov of Kazakhstan won the men's road race.