Habitual first adopters are used to regular bugs in their new gadgets. The bleeding edge often has really weird problems that no designer can anticipate, especially with the intricate computer-controlled systems we use every day. The Nissan Leaf is a new EV that's having a strange problem, owners are going to start their car, and... nothing. Nissan's engineers and Leaf owners are working on troubleshooting the specific problem.
Nissan reports that this bug probably has something to do with the air conditioning unit during the startup process. Troubleshooters have been working with this issue on My Nissan Leaf. "if your car throws the exclamation point car error with the yellow triangle, don't turn it off, drive to your nearest dealer or risk requiring a tow."
Nissan currently has no plans to issue a recall. There is no safety hazard as the flaw merely causes ignition failure. This may change as they firm up their diagnosis. You can read their official press release quoted below.
Nissan has recently become aware of an issue on a small number of Nissan LEAFs with a sensor in the air conditioning system. If this sensor is activated it will illuminate a warning light on the instrument panel and may cause the vehicle to not restart once it has been turned off. We are actively investigating to determine the root cause and what action is necessary to address the issue.
This is not a safety issue as the vehicle will not stop running while being driven but may not restart after being turned off. Nissan is committed to a high level of customer service and satisfaction and is working to promptly address this issue.