Has the W brand but lacks W standards
I was really disappointed at my recent stay at the W SF. I've stayed at other W hotels and the SF branch is far from the W experience I'm used to. The decor dubbed 'trendy' hasn't been maintained well so the hotel looks almost kitschy / borderline tacky. The service was spotty as well. 
Here is a summary of the poor service / experience:
1/ The valet guys were slow in acknowledging help with our bags for checkin. Seemed disorganized in receiving new guests.
2/ There were no slippers in the room and not enough amenities for 2 people. I called to request slippers and add'l amenities from housekeeping and they brought up slippers but instead of add'l amenities, they brought face cloths instead. wth.
3/ I noticed stains on my bath towel and on my bedsheets. Pictures provided.
4/ Upon checkout, there was one person working the front desk at 8am. I'd assumed this would be peak time. When a staff member walked out of the back room, we had assumed she would see the line and help. Instead she pretended she didn't see the line and ignored us when we asked a question. Someone on the floor noticed this rude behavior and quickly came over to assist us.
Overall, here are 2 recommendations to the W SF management:
1/ Train your staff!!! they work in hospitality at a W branded hotel. They are not up to W standards.
2/ Spend some money maintaining your property. also, stains on towels and sheets are not acceptable.
Next time I'm in SF, I will stay somewhere else.