<s>
In	O
software	B-General_Concept
engineering	I-General_Concept
,	O
critical	B-General_Concept
mass	I-General_Concept
is	O
a	O
stage	O
in	O
the	O
life	O
cycle	O
when	O
the	O
source	O
code	O
grows	O
too	O
complicated	O
to	O
effectively	O
manage	O
without	O
a	O
complete	O
rewrite	O
.	O
</s>
<s>
At	O
the	O
critical	B-General_Concept
mass	I-General_Concept
stage	O
,	O
fixing	O
a	O
bug	B-Error_Name
introduces	O
one	O
or	O
more	O
new	O
bugs	B-Error_Name
.	O
</s>
<s>
Tools	O
such	O
as	O
high-level	B-Language
programming	I-Language
languages	I-Language
and	O
techniques	O
such	O
as	O
programming	O
in	O
the	O
large	O
,	O
code	O
refactoring	O
and	O
test-driven	O
development	O
,	O
exist	O
to	O
make	O
it	O
easier	O
to	O
maintain	O
large	O
,	O
complicated	O
programs	O
.	O
</s>
