I am having trouble understanding the landlord's perspective here. Say my tenant just missed 3 months of rent because they could not work during quarantine. Now

I am having trouble understanding the landlord's perspective here. Say my tenant just missed 3 months of rent because they could not work during quarantine. Now, the economy reopens and they get their job back (yes, this is an assumption). Now they are able to pay rent but, because their job is not high-paying, they are unable to pay back the 3 months of debt. I can either waive the debt or evict and find a new tenant. But I lose the debt in either case, so why would I prefer to evict and have to suffer the hassle of finding a new tenant?