I often ask couples I work with to tell me their love story. Their narrative about how they met, fell for each other, and made a series of decisions that led to where they are now tells me a lot about their relationship and their mindset.

As they share each milestone—living together, engaged, married, baby—I ask how they decided to make these big steps.

When I ask how they chose to move in together, it’s often met with a long pause. “I’m not sure,” they may say. “It just sort of happened.” Perhaps they’ll add that “my lease was up” or “his apartment was more convenient.” It’s clear in these cases that people often let themselves fall into the next phase of a relationship without truly considering the “why” behind it.

In the therapy world, this is called “sliding vs. deciding,” a phrase coined by researcher Scott Stanley.

Sliding is a common way that humans make decisions—just letting life circumstance guide us to the next step, hoping things will feel OK once we get there.

Sure, it saves us the trouble of having to make a tough call or think too much about the unknown that is the future. But what’s the trade off?

According to a 2014 study that sampled 252 men and women, “regardless of relationship status (i.e., dating, cohabiting, or married), those who reported more thoughtful decision-making processes also reported more dedication to their partners, higher satisfaction with the relationship, and fewer extra-dyadic involvements.” That means higher commitment, more happiness, and less infidelity reported for those who actively and enthusiastically decided, “Let’s do this!”

It turns out, talking through your plans and commitment level with your partner before finding a shared space matters—especially since it becomes significantly harder to break up once your books are interspersed with hers on the bookshelf or you’ve given up half your shoe collection to make room for his. Sliding into one decision may mean sliding into subsequent decisions just because they’re the natural next step. It’s inertia; I have to keep going because I’ve already started down this path.

So before you make the decision to shack up, consider these questions—and ask them of your partner:

What does it mean for our relationship that we’re moving in together?

What do I see as the next steps after cohabitating?

Why do I feel comfortable making this step?

What am I worried about?

How do I expect that our relationship will change once we’re living together?

How do I hope things will stay the same?

Of course, plenty of couples who slide into decisions end up very happy together. And many who make thoughtful decisions still end up unhappy. You can’t anticipate everything you will want and feel in the future—and sometimes you’ll need to revise your plan. But thoughtful decisions do give you a clear advantage.

Feel free to apply this same reasoning to any major relationship decision: having sex, getting married, having kids. Or major decisions outside of your relationship: accepting a job, pursuing a degree, adopting a pet. Before making any big moves, practice pressing pause and checking in with yourself:

Am I sliding or am I deciding?