With the Focus, Ford is using what I call a "defensive" product strategy. It is not unique to EVs; for example, GM did a similar thing by slapping together the 85 Astro after Chrysler released the Caravan in 84. I have written more on this topic
HERE, but this is a quick summary describing the Focus:
The auto market is pretty well saturated, there is an unreasonable amount of brand loyalty, and mass-market profits depend on volume. If you want to increase volumes in a saturated market, you pretty much have to steal customers from other automakers, which is tough given the loyalty. So automakers are constantly looking for ways to make conquest cars - slightly new product categories that will win over NEW (to them) customers from other brands. (If these conquest cars are low-margin, they have to be non-cannibalizing as well, but that's a separate issue).
In this case automakers like Nissan and BMW have produced conquest cars with the LEAF and i3. They have been very successful in pulling in new owners from other brands. Ford is one of the brands losing customers. Not to mention they needed a compliance car anyway.
All Ford was trying to do was to stop the bleeding as cheaply as possible. The cheapest way to create a car is to make it a version, so they created a version of the existing Focus. Most of the specs (when it was first released, anyway) very closely matched the LEAF. This was just a defensive maneuver to keep Ford loyalists buying a Ford rather than going to Nissan. They are letting Nissan doing most of the work to pave the EV way by dealing with governments, advertising, charging infrastructure, dealer training, ride-and-drive sponsorship, and the like.
Of course by making the Focus EV a cheap defensive version, they made some compromises, like stuffing batteries in the trunk since it was a conversion and there was nowhere else to put them, and leaving off DC charging because that was too hard (though I have heard the car was engineered to support it - marketing, infrastructure, standards, etc are likely far bigger issues) and perhaps they were hoping the whole zero-emission mandate thing would go away again.
For now, Ford doesn't have to sell too many EVs. The Focus EV is selling in very tiny numbers, but when combined with their quick, cheap, PHEV conversions (C-Max and Fusion) they are not really doing so bad and, for now, getting all the credits they need - and they have spent far less than Nissan and BMW (something very important to Ford; they have learned they can only predict regulations and demand so well and want to stay flexible). Once the Bolt, Model 3 and Nissan LEAF 2.0 are available, their approach will no longer be good enough. They will release a different car in this general category. It will likely be more competitive, but they have said they are going to continue with the cheaper, more-flexible shared platforms (something similar to what Hyundai is doing), so it won't be class-leading. I am more interested to see what they do with trucks and such...
It's not what I would buy, and I have pointed very few people at them. But if you are a multi-car family and don't need DC charging or a big trunk (hey, I didn't have those in my Roadster either), the Focus is a good little platform, electrifying it makes it better, and all the Focus EV owners I have talked to have been very pleased with their cars.