Are these drywall cracks a sign of something serious?

[Miles Stanley]

Hello BP,

I walked through a property the other day and i noticed these types of cracks in the drywall.  The structure was built in 1985, condition of foundation is unknown.  In your expert opinion, do these photos indicate foundation issues or is this just drywall shifting due to framing settlement, etc?  You can tell where the owner tried to fix some from before...some repairs held and others did not.

Thanks,