Many times, new graduates are on the fence about doing an internship versus going into private practice. I have heard several say, “Well, maybe I will go into practice first, and then come back and do an internship.” Although this is not impossible, it is very much the harder path.
Internships and, to a lesser extent, residencies, are designed to fit within a certain career progression. Vet school leads to internship leads to residency. This is rarely deliberate on the part of the program supervisors, but it is a side effect of a number of differences between academia and private practice.
Letters of recommendation. When you are a senior student, you will get letters from specialist clinicians who work with you in that context. If you go into practice, who will write your letters? Your former faculty perhaps, but they haven’t worked with you as a veterinarian- they can only speak to your performance as a student six or more months ago. Your boss and colleagues in practice probably don’t have much experience writing a letter of recommendation for an internship or residency, and this lack of experience shows plainly when evaluators read applicant packets.
Mentoring and advocacy. If you are at an academic institution, you have mentors who know the system and can give sound advice on how to proceed through it. I routinely would get an email from an anesthesia colleague who was on the internship selection committee at their institution asking my opinion on the list of students applying that year from my institution. I knew them and had worked with them, so could advocate for them. The boss at your practice is almost surely not getting that same email.
Money. Oh man, is it addicting to get a real paycheck. I remember going from a resident salary to a faculty salary and thinking, “How am I going to spend all of this?” Fortunately I saved/invested a lot of it, and you should, too. But many people get the big paycheck and realize, “Hey, I don’t have to eat ramen every week!” It is very hard to go from earning a fair salary in practice to a third or less in an internship or residency.
Habits. I don’t agree with this, but I do know program evaluators who are worried about those who have been out in practice coming back to academia with bad habits which will have to be corrected. I know one prominent neurologist who wouldn’t consider an applicant if they had graduated more than 3 years before applying for a residency for this reason.
Ego. Are you prepared to go from being The Doctor to being a cog in the wheel of academic medicine? You have clients who look up to you, even if you’re “the new doc,” you have a certain degree of authority. In an internship, you will have to swallow your ego and be OK being near the bottom of the ladder. I know some programs who are concerned accepting applications from those who have been out in practice too long, because they are worried the applicants’ ego will be too developed to be teachable.
I know some residencies- notably radiology- tend to take a fair number of applicants who have been out in practice for several years. In general, though, most programs will select those who have gone through a more traditional route. You can be successful going out into practice and then coming back into academia, but it is an uphill battle.