Peel bark, clean bark or leave it?

Ok my friends, long question.

Specifically I just received some old bouganvilla that were to be thrown out. The bark is old and neat looking but a little soft almost dry rot like, should this be removed?
Ok, a more general question about bark. I have some other trees (fukien tea, chinese elm) that have flaking bark should this be removed? Ive seen trees that look all clean and nice but I thought aged bark is desirable. Same with junipers do people strip them for asthetics or is this the proper thing to do? Any bark advice all areas? thanks

Arno

The bark thing can be aesthetic, but it can also be good cultural practice. Rough, dry, etc. bark can harbor insects.

The bougainvillea bark is normal. I would NOT rub it off.

Bark, like our skin, is a protective shield against all kinds of infections that might affect the interior of the organism.

Can you show a picture though? You mentioned the bougie looks like it´s rotting? If so, I´d recommend to clean up all the dead wood and treat it. But that´s me in my climate.