Personally, I don't think it'll be a sales flop in specific terms: it won't sell well in general terms, nor in comparison to its best-selling cars (the 458 Italia sold about 15k in six years, with the 458 platform generally making it to 20k), but Ferrari will probably sell every one it plans to build. Which will be in the hundreds a year, maybe as much as two a day on average early on.
That's not just because it is generally a poor piece of design both in overall look (too tall, too slab-sided, too much of a Leaf rip-off) and in general detail (pug underbite, droopy front-fell-off-a-Bricklin, pooping out a Corvette-lighted Saab 9000, thumb-operated battery cover at random on the sides, hey why not park the wipers like that, no design lineage from any other Ferrari as far as I can make out), but because it's ugly and it's $640,000.