Many consider Philip's rule a success, because although throughout his reign many tried overthrow him in the name the Protestants, his religion of Catholicism remained steadfast throughout his empire.
He maintained rule over one of the largest empires known to man
Under his rule, and with the help of the Holy league, he stopped the influence of the Ottoman empire
He created the largest and most formidable navy of the time TWICE
Because he was an avid art and literature lover, under his rule Spain made some major advancements in those respective fields.
Philip faced financial struggles throughout his reign as king. He was constantly having to borrow money from other countries and caused spain to go bankrupt a total of four times.
The King's foreign policies never included anything that would help relieve the huge debt that he was in.
His taxes on countries other than Spain were said to be unreasonably high.