Mary Portas has listed her 10 worst customer service crimes, and says when it comes to uninformed shop assistants, "DIY shops are the worst".
The self-styled retail guru named her worst irritants when it comes to retail in an article for The Daily Telegraph:

1. Keeping too few tills open

2. Mute cashiers - Ms Portas says they've "lost basic communication" and don't even say the price

3. Plugging inappropriate offers - WHSmith is named as the worst offender

4. Assistants who don't know their stuff - "DIY shops are the worst," said Ms Portas. "Bank Holiday Monday in Homebase? I'd rather stick pins in my eyes."

5. Shoddy fitting rooms

6. Too much stock on the shop floor

7. It's a shop, not a social club - gossiping staff make customers feel "invisible"

8. Signage overload

9. The hard sell

10. Annoying phrases - "If it's not out on the floor, we haven't got it" is one of the worst

In her last series, Mary Queen of Shops, Ms Portas paid a visit to several high street shops, including DIY independent Lightwater Homecare, in a bid to turn struggling stores around.

A new series for Channel 4 sees her take on shoddy service as a mystery shopper, visiting big retail brands in disguise. Several episodes of Secret Shopper have already been filmed, with one looking at sofa superstores.

There are plans to shoot more episodes, which may feature DIY stores or housewares shops. Any retailers who might like to feature on the show can call Optomen Television on 020 3227 5900.

Secret Shopper is on Wednesdays at 9pm on Channel 4.