A company conducts campus placement in about 10 to 12 colleges. Overall they shortlist about 100 to 110 students from all the colleges and calls them for next round of interviews. After over 2 to 3 months of drama they provide offer to 10 to 15 students just in case if someone backs out. The position and salary is not that great but for a fresher its an average pay job with average skills required for that job and any graduate with average score can do the job. So why waste so much time ? This is not a one-time deal they do this annually ? Is this normal or they just do it so the HR has something to do for that period ? Why waste so much resources for this ?
You didn't mention what kind of job this is, but I assume that it's a Junior Position.
110 Interviews for 10 positions is already stretching it, a lot. Its not uncommon for companies to interview hundreds of candidates per position, especially when they're big companies.
A junior position or a job "that everyone with a degree can do" is usually just a stepping stone to more responsibilities in the company. They want to make sure to get a decent employee who is useful in the role, a good fit for the company culture, gets along with prospective coworkers and (maybe) is fit to eventually moving to a more senior position. All of that takes lots of screening and usually lots of candidates.
Resources spent on finding the proper candidate as opposed to someone that could cause issues later aren't wasted. Hiring is a notoriously expensive process.
So why waste so much time ?
- Each college requires a specific number of interviews in order to take part in their campus placement activities
- The company isn't 100% sure how many positions will be available
- The company really wants to hire the best people
- People generally like to feel selected/important, the lower the offer rate the more they might feel this way
- Logistically it might be convenient - at my University, most companies have on-site interviews the next day. It is very quick/easy/cheap for them to schedule a full day of 30 minute interviews from the resumes they collect after the job fair
- It is much easier/cheaper to interview 20 people this way than to bring 10 to the company for onsite interviews
- Enough hiring managers are affiliated with all the universities and want to "interview a lot from my school"
The reality is every company has different approaches to recruiting. It might just be some manager having a power trip, too, it is hard to say.
In some companies HR gets quite top heavy and this sort of thing becomes the norm. I've seen a company go from one HR who was a very busy person for several years, to within 2 months having 6 HR personnel all trying to look busy.
It's pretty much up to each company and how their HR operates. My own opinion is that HR can at times become an industry within an industry not always for the benefit of the company and if not controlled properly they start making their own work. But that's just my opinion from an outsiders perspective.
If a company is interested in getting the top performers, this is the only feasible approach.
Sturgeon's Law states that 90% of everything is crap. This is true for many things -- also, and in particular, with people you hire.
It is a common misbelief among tech companies that they hire only the best of the best of the best. Almost every company with a bit of self-esteem says that. The fallacy is: "We interview 100 people and only hire the best two.". That's not how you get the best.
It has been known for many years (even Forbes and the NY times meanwhile noticed and wrote about it) that the best of the best are already employed. They are not on the market.
Companies only interviewing those who are looking for a job will eventually of course also find a few good ones, but they will not find the best, or the best of the best. For the most part, they will interview and re-interview the same people who keep applying for jobs unsuccessfully over and over again. Those are however exactly the people that they don't want.
If you want the best of the best, and in particular if you want them affordably, you must catch them before they leave university. Otherwise, you have to take what remains, or you have to pay very, very dearly.
Once employed, you will need to make an offer that is able to convince them to leave their current job, which means it has to be a quite good deal.
You can however only catch the good ones if you know who they are, which means you have to interview a lot of people, even if you only have one or two vacant positions, or maybe do not even have a position open at all (it may be worth creating one).
One possibility is the company is hoping not only to get the best candidates now, but also to get a large pool of prospective employees in the future to be familiar with the company, and possibly to consider the company in the future when they are applying for more experienced jobs.
If you have a good interview process with a company, even if you don't end up getting (or taking) a job with them, it's very possible you will have a positive opinion of that company afterwards. As such, you may be more likely to consider that company when you are looking for jobs three to five years later - when you've got enough experience to get that next level position. Think of it as relatively inexpensive advertising, that does have an additional benefit (of giving you a slightly better incoming class).