<s>
The	O
law	B-General_Concept
of	I-General_Concept
conservation	I-General_Concept
of	I-General_Concept
complexity	I-General_Concept
,	O
also	O
known	O
as	O
Tesler	O
's	O
Law	O
,	O
or	O
Waterbed	O
Theory	O
,	O
is	O
an	O
adage	O
in	O
human	O
–	O
computer	O
interaction	O
stating	O
that	O
every	O
application	B-Application
has	O
an	O
inherent	O
amount	O
of	O
complexity	O
that	O
cannot	O
be	O
removed	O
or	O
hidden	O
.	O
</s>
<s>
While	O
working	O
for	O
Xerox	O
PARC	O
in	O
the	O
mid-1980s	O
,	O
Larry	O
Tesler	O
realized	O
that	O
the	O
way	O
users	O
interact	O
with	O
applications	O
was	O
just	O
as	O
important	O
as	O
the	O
application	B-Application
itself	O
.	O
</s>
<s>
The	O
book	O
Designing	O
for	O
Interaction	O
by	O
Dan	O
Saffer	O
includes	O
an	O
interview	O
with	O
Larry	O
Tesler	O
that	O
describes	O
the	O
law	B-General_Concept
of	I-General_Concept
conservation	I-General_Concept
of	I-General_Concept
complexity	I-General_Concept
.	O
</s>
<s>
The	O
interview	O
is	O
popular	O
among	O
user	B-Application
experience	I-Application
and	O
interaction	B-General_Concept
designers	I-General_Concept
.	O
</s>
<s>
Larry	O
Tesler	O
argues	O
that	O
,	O
in	O
most	O
cases	O
,	O
an	O
engineer	O
should	O
spend	O
an	O
extra	O
week	O
reducing	O
the	O
complexity	O
of	O
an	O
application	B-Application
versus	O
making	O
millions	O
of	O
users	O
spend	O
an	O
extra	O
minute	O
using	O
the	O
program	O
because	O
of	O
the	O
extra	O
complexity	O
.	O
</s>
<s>
Thus	O
,	O
when	O
an	O
application	B-Application
is	O
simplified	O
,	O
users	O
begin	O
attempting	O
more	O
complex	O
tasks	O
.	O
</s>
