Poolish

People usually use a poolish to improve flavor.  It will also have some effect on dough development, and maybe the final texture of the loaf.  But a straight dough will rise as well as any kind.  If you use instant dry yeast, you don't even need a 5-10 minute proof.

Reinhart's Bread Baker's Apprentice is a good introduction to pre-ferments in general.  A poolish is one type of pre-ferment (wetter than the final dough).  There are also pre-ferments that have the same ratios as the final dough, and pre-ferments that are dryer than the final dough.  Whether these make vast amounts of difference or just keep hobbyists entertained is hard to say.

- Is Poolish (preparing yeasts the night before baking) recommended for all breads? 

Yes. But you are free to not follow that recommendation. It's a very old method of time management in baking.

With poolish fermenting when the baker sleeps, in the morning, the bread dough mixed with poolish is ready within an hour or so. Otherwise, straight bread dough (without poolish) would take longer to mature, 2-4 hours. So, in baking Poolish allows you to save on time needed to prepare your bread dough. 

- Does it provide better rising then cultivating for 5-10 minutes just before mixing ingredients?

It depends on the flour. If the flour that you are using is strong bread flour, then poolish will help bread rise taller. Poolish modifies gluten, weakens it somewhat, so it stretches better as the dough ferments.

IF the bread flour is rather weak, then no. It will rise better with stiff preferment, like biga or sponge.

Average quality flours will give you the same rise with poolish or without. Usually, when you use poolish, you need less yeast overall, so it saves you a bit on the cost of yeast.