As an in-universe explanation, that is.
In TNG, the Enterprise started off with the curvaceous Type-7 shuttle. It existed both as an interior set and exterior set piece, but the latter was difficult to make look right and they eventually ended up having an awkward looking wall piece that they only ever shot from one side. To compensate, in the second season they came up with the Type-15 shuttlepod, which was smaller and angular, making it easy to shoot in and around both in the shuttlebay and whenever they needed it on a planet. This became the "stock" shuttle set they used whenever they needed to see it from the inside and outside.
In the fifth season of TNG, they introduced the Type-6 shuttle, which was slightly less angular AND slightly curvaceous, and could be moved around to shoot in various sets. A new shuttle interior was also created, which was slightly larger than that of the set piece, though the latter had enough detail to be used AS the shuttle for whenever they needed to shoot people entering and exiting the aft door. The interior set also ended up replacing the interior of the Type-7 shuttle, which was still seen occasionally via stock footage. The shuttlepod stuck around though, being used sporadically and sometimes paradoxically when a larger shuttle would've made more sense ("Power Play", having been retrofitted to include a third seat).
By the seventh season though, the 'pod had largely disappeared. After "Descent", it was featured that year in a DS9 episode ("Second Sight") and the interior set would eventually be donated to DS9 to show up as the Maquis fighter cockpit and then the interior of the Defiant's shuttlepod for the third season, after which it too disappeared... Thus ending the saga of the little two-person shuttle that could.
But what of any in-universe explanation? There seems to have been a very narrow window that Starfleet thought a mini shuttle would make sense. Both before TNG and after, everyone seems to prefer using "full size" shuttles, to the point that shuttles got big enough to basically be runabout-sized starships. Even the NX-01's shuttlePODs were capable of seating three with room for more crammed in the back. In the original Voyager writer's tech manual, Rick Sternbach thought to include four shuttlepods as part of the complement in addition to two standard shuttles and the fabled Aerowing, but this was never visualized. Nowhere but in this small period of time does Starfleet really think that a small auxilliary craft with room for 2-3 people and not much else would be a good idea.
Are we looking at an experiment gone wrong? Somewhere in the early 2360s, an engineer said it'd be great to have an auxiliary craft for just a couple people who needed to get only themselves around at STL speeds and figured to equip the fleet with a bunch of them? Only to realize by 2370 that anyone would rather use a larger shuttle of the Types 6-11 even if it's just one person aboard? Would the economics of construction of the full size shuttles mean that Voayger would pull out of drydock with four Type 9s instead of four shuttlepods (and no Aerowing)? Or did it simply make more sense for the resources of shuttlepods be continued to be dumped into the ubiquitous workbee program?
Mark
In TNG, the Enterprise started off with the curvaceous Type-7 shuttle. It existed both as an interior set and exterior set piece, but the latter was difficult to make look right and they eventually ended up having an awkward looking wall piece that they only ever shot from one side. To compensate, in the second season they came up with the Type-15 shuttlepod, which was smaller and angular, making it easy to shoot in and around both in the shuttlebay and whenever they needed it on a planet. This became the "stock" shuttle set they used whenever they needed to see it from the inside and outside.
In the fifth season of TNG, they introduced the Type-6 shuttle, which was slightly less angular AND slightly curvaceous, and could be moved around to shoot in various sets. A new shuttle interior was also created, which was slightly larger than that of the set piece, though the latter had enough detail to be used AS the shuttle for whenever they needed to shoot people entering and exiting the aft door. The interior set also ended up replacing the interior of the Type-7 shuttle, which was still seen occasionally via stock footage. The shuttlepod stuck around though, being used sporadically and sometimes paradoxically when a larger shuttle would've made more sense ("Power Play", having been retrofitted to include a third seat).
By the seventh season though, the 'pod had largely disappeared. After "Descent", it was featured that year in a DS9 episode ("Second Sight") and the interior set would eventually be donated to DS9 to show up as the Maquis fighter cockpit and then the interior of the Defiant's shuttlepod for the third season, after which it too disappeared... Thus ending the saga of the little two-person shuttle that could.
But what of any in-universe explanation? There seems to have been a very narrow window that Starfleet thought a mini shuttle would make sense. Both before TNG and after, everyone seems to prefer using "full size" shuttles, to the point that shuttles got big enough to basically be runabout-sized starships. Even the NX-01's shuttlePODs were capable of seating three with room for more crammed in the back. In the original Voyager writer's tech manual, Rick Sternbach thought to include four shuttlepods as part of the complement in addition to two standard shuttles and the fabled Aerowing, but this was never visualized. Nowhere but in this small period of time does Starfleet really think that a small auxilliary craft with room for 2-3 people and not much else would be a good idea.
Are we looking at an experiment gone wrong? Somewhere in the early 2360s, an engineer said it'd be great to have an auxiliary craft for just a couple people who needed to get only themselves around at STL speeds and figured to equip the fleet with a bunch of them? Only to realize by 2370 that anyone would rather use a larger shuttle of the Types 6-11 even if it's just one person aboard? Would the economics of construction of the full size shuttles mean that Voayger would pull out of drydock with four Type 9s instead of four shuttlepods (and no Aerowing)? Or did it simply make more sense for the resources of shuttlepods be continued to be dumped into the ubiquitous workbee program?
Mark