Ads doesn’t guarantee 100% sales.They increase the probability of sales.Customers attracted only to the photos star rating & most importantly the price.if the price is too high it will not sell even if you advertise.The amazon tutors brainwash new sellers to advertise more often.well ads increases exposure.But you have to do basic home work on product photos description features ,store promotions etc.it’s the photos we sell on eCommerce platforms.You should download advertising reports from your seller central dash board by clicking the reports menu.you can now differentiate between best performing and worst performing keywords and search terms.create manual campaigns and add best performing keywords in positive and under performing keywords in negative.it will considerably reduce your ad expenses.once a lady from amazon called me when i was driving.she tried to brainwash me.she even mentioned your daily ads expense are such low.which pissed me off.because it’s our hard-earned money.& they are upset because they don’t get Rs-500 ad monthly from me.my products are so popular .who needs your shitty ads