The movie comics actually made the movies make sense... so it is a pity that there were no epilogue/sequel comics from TF3, and not prequel comic for TF4 (and no indication of an adaptation comic either).

But ultimately it comes down to the sales numbers, and the Movie comics didn't do too well...

The first movie adaptation did well in June 2007, with all four issues being in IDW's top 5 for that month, coming in at #109-123, at 18,000 to 16,000 units.

The sequel to the first movie did okay as well, with the middle issue in July 2008 being the fourth best IDW title at #157 with 13,000 units sold to comic shops.

The Defiance prequel to the second movie in March 2009 was now down to 10,000 units at #150 & #151, with 9 other IDW comics doing better that month.
The Alliance prequel was even worse at 9,000 units at #159.

For the second movie, in July 2009 the movie adaptation was #172 at about 10,000 units, with 9 other IDW comics doing better (including AHM).
The epilogue comic for TF2 in September, came in at #174 at 11,000 units, with 7 other IDW comics doing better.

The TF2 sequel/epilogue in March 2010 was now down to less than 9,000 units at #191, with 7 other IDW titles doing better (including several GIJoe comics, which is supposed to have a smaller fandom with less toy sales and fanclub/convention attendees).

TF3 had two prequels as well, dropping down to 6,000 units each in March 2011 and sitting at #259 and #268... barely making it into the top 300 list. By the end of their mini-series, they were down to about 5,000 units each, and almost 20 other IDW titles were doing better.

The first three issues of the TF3 adaptation in June 2011 were staying down (like a Coles commercial) at about 5,500 units each, at #270-280, with 16 IDW titles doing better that month.

My thinking is that on Transformers Movies, the trend suggests that it isn't worth doing by IDW at all anymore. They have a small, limited number of staff, who can get better return on their investment by doing something else instead... no matter what it is.


I also think that people probably avoided the comic, assuming that it would make as little sense as the movies... but if IDW marketed their comic adaptation as "making sense of the theatrical movies", they might get more interest (like people who go out and buy the book of a movie after they see it). But then, Hasbro and Paramount would probably prevent IDW from promoting that, as it would impact on their much-bigger revenue earners.
Which is going to get priority, the multi-billion dollar movie franchise, the multi-million dollar toy franchise, or the multi-thousand dollar comic series.