The relatively unsophisticated and ad-hoc nature of sessions is due to the fact they weren't part of the initial design, and had to be developed, with minimal disruption to the main line, by a third party (Citrix Systems) as a prerequisite for their terminal server product for Windows NT, called WinFrame.
Relativno nesložena i ad-hoc priroda sesija jest posljedica činjenica da nisu bile dio izvornog dizajna, te da su trebale biti razvijene s minimalnim ometanjem glavne linije razvoja, i to od strane treće ruke (Citrix) kao preduvjet za njihov terminalski poslužitelj proizvod za Windows NT, zvan WinFrame.