Lack of transparency on the product development and project management.
Inexperienced senior management - Many of them lack managerial, communication and conflict resolving skills. Power games happen very often however people who've been working for + 2 years don't bothers to report it to HR or founders as any of these will have no impact on their behaviours - Double standard applies on "old employees" who are filling the key roles.
Questionable hiring/promotion process for key roles - the employees already know who will likely get the position or be promoted internally (external candidates end up wasting their time no matter how qualified they are for the role). In opposite, if you are in the manager or mid-senior level, you will pretty much have no chance to climb the radder in the organisation without the right people on your side.
Politics - The biggest problem.
Lack of diversity, gender pay gap - The diversity matter got improved a span of years but the company still have a lot to work on. While being highly proud of 50/50 ratio of male/female employees, no big improvement on the gender pay gap.