Moral of the Story: The client isn’t always right.
The OICW – Objective Individual Combat Weapon – was part of a program in the 1980s and 1990s to replace the whole lineup of US small arms with a consolidated group of new high-tech ones.
The XM29 (as it was designated) was a 15-pound clumsy and awkward boat anchor of a weapon. While the many capabilities may have looked good on paper, the XM29 was pretty awful for regular soldiering – heavy to carry and slow to use.
The OICW was basically [supposed to be] a mashup of a 5.56mm carbine with a semiautomatic 20mm grenade launchers.
The grenades could be programmed with a laser rangefinder to detonate at any desired range. Just past walls, just inside windows, that sort of thing. The weapon had a big multi-function optical sight that would allow both day and night vision and a bunch of other features.
[12:21] https://youtu.be/Ez4DPz-Eo88?si=
Edit: Turns out Daewoo made their own version the k11 (see below)
Tldr: They basically wanted the Swiss army knife approach for supply chain reasons. Plus they hoped to get better rifles and to shoot grenades at people behind walls out of the program.
Thx VM!