Soft reset after application install - must or best practice?

[RED_RAIN]

I do a lot of ROM upgrades and when going through the install process there are some apps that say you should do a soft reset after installation and some that don't.

I know some posters soft reset after EVERY app install.
Some after EACH one that asks. (this is what I'm currently doing, install all that don't require soft reset, then do soft reset after each one that says I should)
Some that may do all installs and only reset after ALL apps have been installed.

So what's the answer, is it a best practice to do one of the above or is it a requirement in how they are installed for them to function correctly.

I just know I spend a lot of time waiting for the phone to reboot after each soft reset.