Their small programming team allowed for a larger design group. The programmers also found the engine accommodating,[51] though it took about nine months to acclimate to the software.[41] Spector felt that they would have understood the code better had they built it themselves, instead of "treating the engine as a black box" and coding conservatively.[51] He acknowledged that this precipitated into the Direct3D issues in their final release, which slipped through their quality assurance testing.[51] Spector also noted that the artificial intelligence, pathfinding, and sound propagation were designed for shooters and should have been rewritten from scratch instead of relying on the engine. He thought the licensed engine worked well enough that he expected to use the same for the game's sequel Deus Ex: Invisible War and Thief 3.[52] He added that developers should not attempt to force their technology to perform in ways it was not intended, and should find a balance between perfection and pragmatism.[42]