Van Garderen came into the season with ambitions of a top-three spot on the Tour de France podium but he fell away in the mountains to finish 29th overall in Paris.
"He's just in a slump. I'm not going to describe what that means. He's not performing. That's obvious."
Van Garderen was earmarked as a talented U23 rider and he burst onto the scene at WorldTour level in 2012 with fifth in the Tour and the white jersey. He won the Tour of California the following season and picked up his second top-five finish at the Tour de France in 2014, still aged 26. In the time since then he has won races but failed to back up on his Tour success. He abandoned the race in 2015 through illness and BMC Racing signed Richie Porte to co-lead the team this year.
BMC have invested in van Garderen's talent and Ochowicz stressed that the rider, who was once seen as the natural successor to Cadel at BMC, still had their faith and support.
"He's certainly an exceptional athlete and he's been gifted with an extraordinary cycling body, however you want to measure that. He's done some great things in cycling but he needs to do something more, not just for us but for himself."
In hindsight, sending van Garderen to the Vuelta was always somewhat of a gamble. Physically and emotionally he had prepared for the Tour de France and little after that. He announced before the Tour that he would skip the Olympics, and he and his family are expecting their second child later this month.
The team stated before Spain that Samuel Sanchez was their leader and that van Garderen would be there to support and try for stage wins. The message was clear, at least to the public, that he was riding without pressure.
When asked if it was the correct call to send van Garderen to Spain Ochowicz replied: "Yes. Otherwise you're ending your season in July. He can do one-day races but he's not really a one-day racer and it's not what he really enjoys. He's a Grand Tour rider and it's not like he was the only guy to do the Tour and then do the Vuelta. Pretty much all the contenders went. It was good for him to do another three-week race rather than going to San Sebastian or the Canadian races."
This winter is pivotal in van Garderen's future. He is still just 28 – relatively young in terms of Grand Tour years but with Porte's position cemented after a top-five in the Tour, van Garderen may decide to turn his focus towards a Giro d'Italia bid or a Vuelta. His Tour days are certainly not behind him but over the coming months something must change, whether it's training, build-up or goals.
"When we see the calendar we'll sit down and go through it. He's going to start his training up again in October and he'll get some miles on the road and do some gym work.
"We are so far away from that," Ochowicz said when asked about how Porte and van Garderen would be deployed next year.
"That's a long way off and I don't want to make any prediction. We've not seen the routes yet."
One rider BMC Racing have been linked with in recent weeks is Diego Rosa, who is out of contract at Astana.
Reports earlier this year indicated that he was on his way to Team Sky but that deal now looks off, with BMC now in the driving seat. Movistar and Astana have also been linked to the rider who recently escaped a ban after an anti-doping whereabouts violation was overturned.
"He's a good rider. We've no commitments just yet at the moment. We were talking to him but our door is pretty much shut. We're still examining who we will keep and who will leave. We're almost at the end of that cycle but there's still a little manoeuvring. I still think he's out there. He's an option."