Many airports, hotels and other public places advertise free wifi, but in a significant fraction of them, the wifi does not work, e.g. in Doha Airport. One view about this is that you get what you pay for. On the other hand, the claim of providing free wifi makes people try to connect and wastes their time. Everyone would be slightly better off if the non-working wifi was not advertised – the advertiser would save the cost of printing the „Free wifi” signs and the visitors would save time.
It is cheap for the service provider to check whether the wifi is in fact working – just program a few cheap used smartphones to periodically try to connect to the wifi and send a notification to IT if the connection attempt fails. The connection failure may even trigger an automatic restart of the router.
Some airports may have wifi available, but only to a restricted group of people. For example, in India, connecting requires a local phone number, which most international travellers do not have. In Singapore and Shanghai airports, the wifi requires either a local number or scanning one’s passport in a kiosk, and the kiosks are sometimes out of order. Again, looking for the kiosk and trying to scan wastes time.
Intermittent wifi may be better or worse than none, depending on what fraction of time it is available and people’s average time cost of trying to connect.