What if I don't wash my hairs with shampoo properly after hair transplant?

Greetings, Please see below. 
Washing your hair after a hair transplantation is an important step for restoration.  We usually have our patients start spraying hair with lactated ringers with liposomal ATP as well as other growth factors twice a day to help your hair process start ASAP.  Actual hair washing usually takes place several days after the procedure.  There are several advantages to this approach:
Healing improvedDecreased inflammation and rednessImproved blood supply and uptakeBest,
Anil Shah

If you don't wash your hair, there will be bacteria and oil build up.  There will be thick scabbing.  It is important to follow your doctor's recommendations.

It is very important to cleanse the scalp as directed after a transplant. Bacteria, yeast, and other organisms can grow. The scabbing should definitely be resolved by this point. I would recommend lathering the scalp with baby shampoo, gently massaging the scalp with your finger tips- not finger nails, letting the lather sit for 10-12 minutes then rinsing with a slow running shower or cup of water. Repeat daily or twice daily until scabbing is resolved.

Washing, that cleans debris and bacteria from the skin surface is important in promoting normal healing.

If you are a month from surgery and you still have scabs, I recommend that you wash rigorously so all scabs come off in 1-2 washes.

Washing is critical to achieving a clean, crust free appearance and minimizing the loss of grafts. An FUE is treated just like a regular hair transplant with regard to the recipient area, but the donor area has open wounds which require daily washing with soap and water. Within 3 days of surgery, you can resume full activities, heavy exercises if you wish. The recipient area requires daily washes as well to keep the recipient area free of crusts. I generally recommend the use of a sponge and supply my patient with a surgical sponge to fill with soapy water and press on the recipient area daily. By repeating this daily, all crusts can be washed off without any fear of losing grafts. IF any crust are present, use a Q tip and dip it into soapy water, and roll it on the crusts and that will lift them off without dislodging them, but never rub them, just roll the Q tip on the recipient crust. I like to see no evidence of any crusting in the recipient area and the crusts from the donor area gone in 7-10 days with daily washing.