Financial Control Creates Options
In career development, the need for options is critical for dynamic growth. When you are in financial distress, you effectively reduce your available options. Your ability to make good career decisions (decisions that reflect more than incremental pay increases) is removed. Career decisions become reactionary, based purely on financial need.
Finances are a huge source of mental noise. It's inevitable. If you struggle to meet your monthly expenses or if your debt is too high, your mental capacity is diminished. Financial trouble can have a dramatic negative impact on your current performance and on your ability to make good decisions.
In addition, your available options are greatly reduced. When money is the primary factor driving your career decisions, you cannot entertain a position or opportunity that might have greater long-term benefit than a higher paying position. You cannot entertain lower paying positions, regardless of the opportunities they present. Remember: I believe that sometimes you should consider trading pay for opportunity. However, that's difficult to do when you are living paycheck to paycheck.
Gaining control over your finances remedies the reduced performance because of mental anxiety and allows you to take advantage of opportunity-rich career moves.