This is what Andy Bechtolsheim essentially said when he talked about why Sun had to develop the SPARC chip. Motorola was just too slow. Great initial architecture not iterated on fast enough.
And when Apple started the PowerPC partnership, they deliberately made sure they had two sources (Motorola and IBM) competing on the same architecture so they wouldn't be beholden to Motorola again (otherwise they were also considering the Motorola 88k)
