I finally reached 100 items in my shop last week. This is my opinion of why 100 is the magic number towards success. I sell vintage collage and doll supplies primarily.
100 items gives customers more paths to follow into my shop. I try to mix up the categories as much as possible, some start with supplies, some vintage.
100 items gives customer more opportunities to bundle purchases to reduce the sting of shipping charges. I have a policy of only charging the actual shipping fees and refunding any overcharge for shipping. I give out alot of $1.00 refunds.
My views went up about 20%. They dipped back down because I dipped down to 87 items. Firdays are a good view day for me. I better get busy listing items again.