Feature Set, Product Quality, and Ship Date

Most of us remember the idea that there are three variables in
software development and no one can define more than two of those.

For example the Marketing Team may pick the feature list and the ship
date but quality will be undefined OR unspecified.

Another example would be the Marketing team says they need something
to show at a certain date and it must be ship quality and the
development team then says we can have 6 of the 9 features done by
that date.

I want to focus on quality. Quality software at least the attribute
that it doesn't corrupt data, doesn't leak private information,
doesn't calculate incorrect results, doesn't report things wrong...
(This list is not complete, just a guide)

If a GUI truncates a field because a textbox isn't big enough then
that is not a quality GUI because the value is not shown. Imagine if
the text box shows you what you will be billed and it shows $99 but
in reality it is $999.

With this fuzzy definition in mind I want to now say that Quality is
always set to high. Since Quality is now a constant there are only
two variables and no one group can set both values.

Marketing can provide the feature list and development the delivery
date.

Marketing can provide the delivery date and development provide the
feature list.