Jonathan Haidt said it well -- we think our brain works like a scientist when it actually works more like a lawyer. Incidentally, your second point echoes one

Jonathan Haidt said it well -- we think our brain works like a scientist when it actually works more like a lawyer. Incidentally, your second point echoes one of the more persuasive arguments I've heard for cofounding teams -- if you can't convince a co-founder to join, will you really be able to build a team and acquire customers?