Moving to a new firm is daunting, sometimes like moving to a foreign country. And like foreigners, they do things differently, and have a different history.
To make an impact in your first 90 days, you need to accelerate your learning about your new firm. After all, you do not have several years to play with. Winging it is unlikely to produce results: instead structure and plan your learning. The starting point is to be aware of your own preferences: some people want everything spelt out in figures, others shy away from such data. Do not let your natural bent cause you to ignore a source of information.
As a newbie, you carry no responsibility for what has happened in the past, nor for what is happening on your first day. This makes it possible to ask questions to staff, clients and contacts as to their views of the firm, and expect reasonable accurate answers. This may raise issues that you need to address quickly, and if you do so you will begin to earn respect and establish a track record in post.
However, if you ask random questions, the process is likely to be ineffective. Best practice is to have a standard list of questions for each category, allowing you to compare answers between individuals and to discern any patterns. Follow on questions can then be asked as appropriate.
People who have worked for or with the firm for a long time can be a particularly valuable source of unofficial history, as can long-established clients. understanding “how we got here” can be important in deciding “how we get there”.