Xerox
Xerox tried several times to get into the computer business, but never succeeded - but in the process, a research laboratory they set up, Xerox PARC, made enormous accomplishements which changed computers forever.
Xerox' first move into computers was to buy Scientific Data Systems in 1969, renaming it Xerox Data Systems, but they could never work out how to make a successful business out of it, and closed it in 1975, losing hundreds of millions of US$.
PARC produced several generations of ground-breaking personal computers, starting with the famed Xerox Alto, along with support technologies such as Ethernet and laser printers.
Xerox attempted to turn that research into a product, the Xerox Star line of workstations, but again could not make a success out of it.
Other computers: Xerox 500 series, Xerox Sigma 9, Xerox NoteTaker, Xerox 820, Xerox 820-II, Xerox Daybreak aka Xerox 6805 PCS aka Xerox 1186.
Other companies, such as Apple, Microsoft, etc went on to turn the PARC research into products that forever changed computers.
