After yesterday’s interview I can’t stop thinking about it. I keep trying to figure out whether I'm really such a loser. The HR directly asked me how I feel about being a loser, since for the past...

No, you are not a "loser" for staying in a role for 3.5 years.
In fact, staying in a position for three or more years is often seen by employers as a... sign of stability and commitment, showing that you can be relied upon to stick with a role rather than "job-hopping".
The interviewer's question was unprofessional and likely intended as a "stress test" or was simply a reflection of their own poor interviewing skills.

Why Staying for 3.5 Years is Normal
1. Skill Mastery: It often takes 2–3 years to deeply understand a role and make a meaningful contribution.
2. Professional Reliability: Many employers prefer candidates who stay long enough to return the investment made in their training.
3. Personal Goals: If you are satisfied with your work and it fits your life, there is no inherent requirement to change roles unless you choose to.

Looking for a salary raise?
Try getting a new more paying job in a different company with your expertise and experience once as an option.

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