Conspiracy theory
#128 : Creator delays releasing product for several years in order to have backers so grateful to receive anything that they don't complain about deficiencies. Now in all seriousness, my ShareRoller bike motor is also very late (started early 2016 if I remember correctly) but it appears to be very close to fruition although tiny incremental delays still occur. I just think the whole process makes it clear that bringing a product to market is no easy task and I've a new respect for those that succeed.