Not necessarily my own view but Playing Devils Advocate ......
Who says its the main purpose?
It's a van that you can camp in. VW could argue its main purpose is transport.
Who says it's a major defect? It doesn't stop you driving the van, it's not safety related so why is it major?
The handbook tells you to shut the roof if there's driving rain ie expect it to leak if there's driving rain & you leave it up as below.
No-one outside VW knows quantity wise how VW view this problem - they may think its one in 1000 vans based on dealer feedback, whereas if you read this forum you might think its 100% of vans. Why would VW warn you not to buy something if in their view there was only a slight risk of there being a problem.
Just comparing with other manufacturers:
Ive had both a lotus & a landrover Defender both with hardtops that leak more than the videos Ive seen of leaking VW roofs. They all do that sir would be typical dealer response.
Even my current Morgan came with a roof that at best could be described as keeping the worst of the water off as long as you are stationary. If you were to query it with a Morgan dealer they would probably express surprise that you even bothered to put the roof up.
Ive got a drive away awning that leaked after the first couple of days use, everyone seems to expect it to leak, bit of seam sealer & its stopped leaking. No-one seemed to think its unreasonable to have to put some sealer on the awning. Put the same tent on top of a van & suddenly it's a disaster.
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