While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a closer look at particularly stock-shaking upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Juniper Networks (NYSE:JNPR) slipped about 3% on Thursday after Mizuho downgraded the network equipment technologist from outperform to neutral.

So what: Along with the downgrade, analyst Matthew Hoffman lowered his price target to $26 (from $32), representing just 3% worth of upside to yesterday's close. So while contrarian traders might be attracted to Juniper's price sluggishness in recent months, Hoffman's call could reflect a sense on Wall Street that near-term sector headwinds will continue to pressure the shares. 

Now what: According to Mizuho, Juniper's risk/reward trade-off is pretty unappealing at this point. "Over the past few weeks datapoints have become more mixed regarding domestic capex as reports AT&T may reconsidering its CY14 capex budget have surfaced (MasTec disappointed, Ciena beat)," said Hoffman. "After conducting a series of industry checks, we are now less constructive on 2H14 domestic U.S. spending as it appears both AT&T and Sprint are becoming more conservative with near-term capex." When you couple that downbeat view with Juniper's near-30 P/E, it's tough to disagree with Mizuho's cautious stance. 

Brian Pacampara has no position in any stocks mentioned. The Motley Fool recommends MasTec. The Motley Fool owns shares of MasTec. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.