Not a mistake, but Pentax's decision to market a stripped-down lowest price unit to introduce beginners to the Pentax line. While I don't know Pentax's price structure, the addition of DOF preview and ST to the K1000 turns it into a KM, which differed in price by more than a minimal amount from the K1000.
Originally Posted by David Lyga
The K1000 sold as well as it did for as long as it did on it's builder's reputation and recommendations of numerous old-line photography course instructors.
There certainly were competitively-priced cameras with more features available during the production run of the K1000, but I doubt any could match its well-deserved reputation for reliability [I have no doubt that most of the K1000s in use today have never had so much as a CLA, and have had multiple owners]. Ricoh's KR-5 series comes to mind as a K-mount K1000 alternative: no DOF preview or self-timer [although the KR-5 III sported both], and a vertical-blind shutter providing 1/125 sec. X-sync, but I think Ricoh cameras in general had film transport mechanism weaknesses. The various Cosina-built mechanical shutter units that wear Ricoh, Olympus, Yashica, Nikon and Vivitar nameplates are proving to be reliable units; several have been provisioned with DOF preview and/or self-timer with mirror-up [the Olympus OM2000 even has a true spot meter], and all have 1/125 sec. X-sync.
Thanks and regards,