Note to myself: the pitch changes behaviour.
Connor,
In a test match, for example, the team captains may look at the pitch and conclude that from day three, say, the pitch is likely to "take spin." That is, spin bowlers will from that point will get more out of the conditions and be more effective in taking wickets than faster bowlers. This will affect their decision on whether to bat first or second, if they win the toss.
This only a brief example of the cosiderations involved. In a T20 game, the condition of the pitch will not alter over the three hours or so duration of the match. Hence, it will not be a factor in deciding whether to bat first.
Note to myself: the pitch changes behaviour.