Perpetual futures - Does it always converge to spot price?

Questions:

1) Does perpetual futures price always converge to spot price?

2) Theoretically speak.. if I held perpetual futures for year, since this is zero sum game, would I ever lose the value at risk? Since crypto is volatile and this is mean reversion strategy, eventually my funding rate deposits (or withdrawals) will eventually be zero? (i.e. break even)

3) Any good video tutorials on understanding the math behind perpetuals? I read the binance FAQs but i'd like to see some cases where arbitrage (ex. long spot, short perp. futures) fails