"Space shuttles carry two tons of lead blocks to compensate for design
error"

Plus at least another 3 tonnes of crew and their all-inclusive
required infrastructure.

That's 5 tonnes of mostly dead or inert mass that most often has
little if anything to do with accomplishing most payload deployments,
that which a robotic feature could have managed.

~ Brad Guth Brad_Guth Brad.Guth BradGuth BG / “Guth Usenet”

Good thing India seems to know what they're doing, and thus far China
hasn't exactly fallen behind.

~ BG