The higher you rise up the corporate ladder, the more often you tackle tough issues. High-impact issues are thorny and complex. They require deep focus to unravel their ambiguity. They require time.

But unfortunately, as the value of your strategic insight and expertise grows, so does the number of people who can lay legitimate claim to your time (board members, clients, cross-functional teams, and the growing number of people who report to you). Just as you develop the business acumen and wisdom necessary to understand big problems, you run out of the time necessary to actually solve them.

Studies show that executive “discretionary time” is rarely more than 5-10 hours per week. The rest of your time is pre-programmed — meetings, turning in things requested by others, people walking into your office with a crisis, etc.

This discretionary time crunch is nothing new. Peter Drucker noted the same dilemma nearly 60 years ago (so please forgive his male-centric language):

“Senior executives rarely have as much as one-quarter of their time truly at their disposal and available for the important matters, the matters that contribute, the matters they are being paid for. … If the executive lets the flow of events determine what he does, what he works on, and what he takes seriously, he will fritter himself away ‘operating.’”

If anything, the past 60 years have only made things worse. Researchers in the “Executive Time Use Project” found that executives were “ working alone … just six hours weekly” (out of 55). And recent McKinsey research shows that:

“…only 52 percent (of executives) said that the way they spent their time largely matched their organizations’ strategic priorities. Nearly half admitted that they were not concentrating sufficiently on guiding the strategic direction of the business.”

So when an urgent need for hiring comes along (like the departure of a senior-level employee), finding the extra time needed is deeply, profoundly inconvenient. And this lack of discretionary time is at the root of most hiring mistakes.

Faced with an inconvenient new priority and an already packed schedule, most managers do what they always do — they force-fit the problem solving into the wee slices of open time in their calendars. They quickly skim resumes, trying to glean more information than can reasonably be learned from a document like that. They severely limit the number of candidates they schedule for an interview. During the interviews, rather than delving into all the relevant issues, they skim the surface and then rely on “gut instinct” to make the hiring decision.

And while the “force-fit-it-into-my-calendar” approach might work for some internal business issues, it is disastrous in hiring. Hiring does not lend itself to a razor-thin time slicing approach because you’re not dealing with familiar people. They are generally not your subordinates or colleagues. Job candidates are complete strangers who have no relationship with you (yet). And since both interviewer and candidate lack the context to properly evaluate each other, each plays a game of “best foot forward” and relies far too heavily on unreliable first impressions. Candidates lack the context to truly understand your motivations. And when faced with ambiguity, most people simply nod and smile so as not to appear a fool.

The structure of the typical interview process often discourages frank conversation and rarely leaves time for enough intelligent questions. Hurried interviews are usually superficial, heavy on style, and light on substance. But once hired, work environments quickly demand precisely the substance that went overlooked during the interview. Misunderstandings and failures abound in hiring because when things go unsaid, there’s no shared context to properly fill in the gaps. The gaps are filled instead by dubious assumptions.

Seasoned executives would never give short shrift to a conversation with a new client or key external stakeholder. Instead they would rearrange other priorities and carve out the necessary time. Successful interviewing demands precisely the same approach

This article originally appeared in the Business Journal