what are the cons of using only shampoo?
Don't ever 'only use shampoo'. I'll tell you how it works- when you put shampoo on your hair, it opens the cuticles and the tail of the shampoo is attracted to all of the grease and dirt inside and on your hair. The head of the shampoo is then attracted to water, so when you wash the shampoo off, the head goes with the water and the tail follows bringing the dirt and muck with it down the drain (shampoo under a microscope looks like thousands of little worms). Now, you have got a head of open cuticles and leaving your hair like that will make it very very easy to snap and break off, and prone to excess dirt build up. Using only shampoo will make your hair very greasy, very visibly dirty. It will then become prone to head lice and scabs/infections on your scalp cause by overproduction of sebum in the glands producing dandruff.
Take it from a hairdresser... ALWAYS USE CONDITIONER!
Its better to use shampoo & conditioner. Actually every second or so washes you can get away with only using conditioner because the conditioner will still get rid of most of the build up, and conditioner works to keep hair healthy from damage and such.
Shampoos and conditioners work best when used together. (Not "together" like you mix them together) Read the instructions from the package.
If your like me and just wanted to use only one useage of hair wash, buy a combo of shampoo and condition, you know, like the 2 in 1 combo.
shampoo followed by conditioner works best. shampoo alone sucks all the moisture from your hair