Sometimes there are things that occur only when the moon is full. Let me
give you an example. The government changes the date when daylight
savings time occurs. Without being current on PTFs you will get burned.
(Unless you're in Arizona.)
Let's say that it uses Java or some such thing under the covers to send
hardware alerts or whatnot. And it does some sort of SSL communication. A
PTF could bring down a new certificate to replace one that is about to
Search the following for 'integrity'
IBM fixes a lot of holes. Holes bad enough that they won't put what they
were in the ptf cover letter.
These are things which could affect you even if you're running in a fat,
dumb, and happy environment doing the same application you've been running
for the last 15 years.
Can PTF application cause issues? You betcha. There's just something
invigorating about having to run ENDJOBABN several times a day because a
currently supported version of Sametime, on a currently supported version
of the OS, and both are supported for each other, stops working because
the Java group ptf (several levels down) is too new. (current open