Candidates have two main components they are evaluating and making a decision on: Company and Role

1. Company - founders, investors, reputation, macro-culture, benefits, market presence, resources
2. Role - your boss(es), co-workers, peers, collab partners, resources, expectations (quota, territory, metrics), tools, communication methods and style, chemistry and management style, micro-culture, departmental dynamics.

Research the company - easy enough to do via internet tools.
Research the role/job - hard to do without engaging directly with individuals and leaders inside or recently inside the company.

Studies have shown that job satisfaction is weighted roughly 70/30 in favor of Role/Job.
Do I "enjoy my work", my boss, my team, my clients/prospects, my product or service?
Is my career accelerating, regardless of whether the company is or isn't?

wsj.com

You Should Get to Know a Recruiter Before You Need One—Here’s How
The best time to start building ties with someone who can help find your next job is while you’re still satisfied with your current one.

Kathryn Dill
5-6 minutes

It is hard to network or overhaul your resume in a hurry, and building relationships with recruiters is no different.

Like much else when it comes to career development, the key is to be proactive, hiring professionals say. Even if you aren’t planning to change jobs imminently, you almost definitely will in the future, and maybe sooner than you think.

Building relationships with recruiters now is an investment in that process and a buffer against any unforeseen events that might set it in motion. It can help you recover quickly from a layoff, leave a bad environment or find the best possible fit for your goals and skills as they evolve.

“A lot of job seekers wait until they’re in that reactive panic mode to plant a million seeds, but by the time they come to fruition they’re already frantic,” said New York-based recruiter Laura Mazzullo.

Here’s how to kick off a relationship with a recruiter, even if you’re happy right where you are.

Get clear on what type of recruiter you should connect with.

While recruiters share the broad objective to fill jobs, their responsibilities can vary depending on the employer or client they’re working for. It is important to know which recruiters seek candidates for the types of roles you might be pursuing. External recruiters work for staffing or search firms and often fill roles for a variety of companies.

Corporate recruiters work inside a single organization. Some recruiters focus on sourcing candidates from underrepresented groups or with specialized skill sets.  Start by determining whom you should be talking to based on your skills and long-term goals. Check out recruiters’ LinkedIn and Twitter presences and whether they’re active in groups relevant to your industry.

Some recruiters recommended searching for the agencies that source candidates for a