Its economics in the manor that its non-trivial and time consuming to produce a physical good. A existing factory can take 6+ months to retool, especially if yo

Its economics in the manor that its non-trivial and time consuming to produce a physical good. A existing factory can take 6+ months to retool, especially if you don't want to interrupt its existing output much. Also a bunch of the developments don't pan out for various reasons, like not being able to get the yield high enough to be worth while, requires large amounts of unobtainium, have very restrictive operating requirements not mentioned in press release (such as a 140F auto-ignition temperature), etc.