Get the latest tech news
Samsung not building a cheap Galaxy Z Flip plays into its competitors' hands
Motorola and Honor know how to build good cheap phones.
Half of the issue is price; almost nobody wants to spend $1700 on a folding phone with a plastic screen and a mediocre camera. Once you start charging a lot of money for a phone, you are in direct competition with Apple's iPhone and the army of loyalists who will never be swayed. Motorola, Honor, and plenty of other companies have the benefit of a cheap but talented labor force inside Chinese factories that can build inexpensive products of high quality.
Or read this on Android Central