Why is "/castsequence reset=25/target" used?

Sequences['Boomy'] = { 
PreMacro = [[
/targetenemy [noharm][dead]
/use [noform]!Moonkin Form
]],
"/castsequence reset=25/target Moonfire",
"/castsequence reset=25/target Sunfire",
"/castsequence reset=10 Force of Nature",
"/cast [nochanneling] Starsurge",
"/cast Starfire",
"/cast [nochanneling] Starsurge",
"/cast [nochanneling] Wrath",
"/cast Celestial Alignment",
PostMacro = [[
/startattack
/use [combat]13
/use [combat]14
]],
}

My understanding of how reset works for 25/target: If the macro is not triggered (regardless if the spell fires) fore 25 sec or more reset OR if the targetchanges reset. That info is mute since with only the one spell it should try to fire every time.

As has been stated elsewhere, if you do not have a reset conditional the sequence will some times fail to advance and will stay on the same trigger. reset=25/target bypasses this bug