This one may be quite obvious.
Each year since 2011, the Cardinals have had a starter get hurt either in spring training or early in the season and ultimately miss the vast majority of the year. Adam Wainwright just went down with a groin injury, that should sideline him for at least a month.
Ultimately, the past is the past. But the trade deadline will present another opportunity. It's impossible to speculate who they might target at this point, but we've talked about the potential of them adding a frontline guy such as Shane Bieber or Dylan Cease, or if not necessarily a frontline starter, somebody who is at least proven and has strikeout stuff, which often plays well in the postseason.
With the Guardians and White Sox both expected to contend, Cease and Bieber may be off-limits, but trying for somebody like former Cardinal Lance Lynn wouldn't be a bad idea. And with the outfield not 100% set just yet, it's very possible that somebody like Dylan Carlson could be the odd man out, and therefore be used to land a pitcher.