Re: TI 99/4a
From what I've heard, the original TI-99/4 was hugely expensive when it first came out, and the cost only came down latterly (by a *huge* amount) in the face of Jack Tramiel and Commodore's price war, which drove TI out of the market shortly after, as the 99/4A's design meant they couldn't afford to sell it at a comparable price to the Vic-20 and still make money:-
https://en.wikipedia.org/wiki/Texas_Instruments_TI-99/4A
From what I've read, it was potentially powerful, but massively hobbled by some fundamental design flaws.