Why Certain Titles Are Never Released?

[ColecoFan1981]

Is there any reason a certain title for a certain system doesn't get released despite being shown in certain catalogs that it might?

Examples:
COLECOVISION
005 (2414)
Side Trak (2418)
Spectar (2421)
Wizard of Wor (2421)
Rip Cord (2431)
Mr. Turtle (2432)
Skiing (2436)
Chess Challenger (2438)
Las Vegas (2439 - working title for Ken Uston Blackjack/Poker?)
Tunnels 'n Trolls (2441)
Horse Racing (2442)
Smurf Play 'n Learn (2444)
Smurfette's Birthday (2444)
Dracula (2608)
Sword & the Sorcerer (2619)
Tac/Scan (2635)
Wizard of Oz (2636)

There are many explanations abound as to their cancellations, including but not limited to:
1. Limited programming time.
2. Programming difficulties (on-screen sprite limitations, cartridge ROM space and other considerations).
3. Cost of programming the game.
4. Licensing negotiations.
5. Exceeding release quotas.

~Ben