Good starting pay doesn't translate to consistent or generous pay reviews.
Confusing pay structure makes it difficult to keep track of what you should be paid; it is common for management to 'drop off' hours from your pay, often deliberately because of upper management pressure.
No internal promotions.
Extremely unprofessional rota-management. Shifts are frequently added or dropped without notice. Hours are frequently added-to or dropped-off, again without notice, sometimes even as you work the shift in question. You will have all the hours you can handle during seasonal periods, but find your hours cut in half during quiet times of the year.
Management rarely communicates store strategies, or amendments to working practices; as a store assistant/cashier you will often encounter problems when trying to deal with customers or scanning products, and have to retroactively discover for yourself that practices or products have changed.
Many of these problems arise because of pressure and threatening behaviour from upper management; threats of summary dismissal, or being summoned to HQ for a talking-to (a two hour drive away) from district or regional managers were common.
On-the-job training often translated to simply being left on your own to figure things out. This was especially common with new duty managers, who rarely received training at all (even though our store was meant to be a 'training store'.)
Long shifts with minimal (30 minutes), oddly placed break time. 10am-9pm or later are common. Sometimes you will work from 5am to 3 or 4pm, with NO break until an undetermined time AFTER 12. Simply exhausting. It is also common for managers to close store by 9pm or later, and then be expected in at 6 or even 5am next day, depending on the workload. Sometimes store assistants are expected to do this also, with accusations of 'not being a team player' or disciplinary action if you attempt to assert your rights.
Just as there is little information flow downwards, so there is no upward flow at all. There is an ingrained company work ethic and expectation for all employees to complete all necessary work regardless of how long it takes or what your written shifts are. You stay until everything is done, or you find yourself getting disciplined and eventually dismissed if you assert your rights, complain, or are simply too exhausted to work effectively.