Annual rings

You can count from the annual circles of the stump how old the tree has been before the trunk was cut down. You can also see from the annual cicles how bad or favorable the weather conditions has been during its growht.

This piece has grown close to sea, only few meters from water and constantly under northern west winds.

It's different with people. You can't say how old she/he is or how life has treated her/him without interviewing even though you were expert on psychology.