Here's a piece of advice if you're going to a Rihanna concert, you don't have to be on time, especially when RiRi doesn't seem to be concerned with starting her shows on time AT ALL.

The 'Stay' songstress is continuing her Diamonds World Tour in Europe and kept fans waiting for two hours at her concert in Antwerp, Belgium on Wednesday (June 5). C'mon, Rih! That is seriously disrespectful!

The bad news doesn't end there either. Not only was Rihanna more than fashionably late for her show, but fans said she delivered a less-than-enthusiastic performance and let her backing vocals do much of the singing for her. Bad form, girl. Bad. Form.

A Belgium music critic, who was unlucky enough to be at the show, wrote (via Entertainment Wise), "There was a wall of reinforced concrete between Rihanna and the public at Sportpaleis. The pop icon played almost two hours on autopilot...it had the effect of a Valium overdose." Yikes. Comparing a pop star's live show to a drug used to treat insomnia is probably the furthest away from a compliment as you can get.

We would imagine a world tour is taxing on your body, but Rihanna seems to be doing what she does best... burning the candle on both ends. The day before she was shopping a Chanel and having dinner with fashion designer Azzedine Alaia, the guy responsible for her amazing Grammys dress this year.

RiRi, if you're going to be traveling around the world on tour, maybe save your sight-seeing and shopping for another trip so you're in tip-top shape for those fans who pay money  to go see you. Just a tip!