Yeah, and it does them no favours.
DTV's used to be a mini-event for fans of superhero animation. All of the following got a significant marketing push and received much more attention:
Batman & Mr Freeze: Sub-Zero
Batman Beyond: Return of the Joker
Batman: Mystery of the Batwoman
The Batman vs Dracula
Teen Titans: Trouble in Toyko
While many of them were far from perfect, you can still see the effort and time that went into them.
I mean, even the Scooby DTV;s were heavily hyped, ala Zombie Island/Witch's Ghost. Now, you blink and you'd miss them. Obviously this same push was present at the beginning of the line with Superman: Doomsday and for a while after. However, they started cranking them out and as the years went on the quality dipped and the interest waned. They barely get one out before they are pushing the next a few weeks later.
Mass production, low budgets, moderate profits.
That seems to be the motto and it's kept the line afloat, but quality is key and they are definitely slipping with the animation.