the first half hour is free, means that people use them for a journey and then lock them up.
London has the free first half hour too, and that spelt problems, since it upset the budgeting. The scheme had been forecast to have enough charged income together with the sponsorship to cover the costs.
In practice virtually everyone confines their use to the free half hour so there's virtually no usage income. In addition the first sponsor, Barclays, weren't happy with the advertsing value, so first reduced what they paid and later dropped out completely. They're now with Santander who are pretty astute so are unlikely to be paying more than Barclays ended up paying.
The Paris Velib scheme which lead the way was a disaster, in no time half the bikes were either missing or broken down. It ended up costing so much that the operator, experienced company J C Decaux, said it would pull out if not given far more money, so that had to be fiddled from the Paris budget somehow. It also suffered from bikes being left at the foot of Paris' steep hills, resulting in having to buy some vans and hire crews to pick them up all the time to take them to where needed.
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