Halejah Sourab states that IT ROI is not a sensible measurement / decision basis because the effect of IT does not only appear in financial aspects or is so distributed that it is impossible to isolate.
Unfortunately he argues for other measurement values, but does not specify what it could be
Currently adding a column to a table with a non-NULL default results in
a rewrite of the table. For large tables this can be both expensive and
disruptive. This patch removes the need for the rewrite as long as the
default value is not volatile. The default expression is evaluated at
the time of the ALTER TABLE and the result stored in a new column
(attmissingval) in pg_attribute, and a new column (atthasmissing) is set
to true. Any existing row when fetched will be supplied with the
attmissingval. New rows will have the supplied value or the default and
so will never need the attmissingval.
datasets like Wikipedia Data Dumps, 2000 Movie Reviews, & UPC Database are difficult to recreate, have high levels of accuracy, are valuable...as this becomes easier to access, the value of these datasets decreases over time.