diff --git a/lib/client.js b/lib/client.js
index c980ab2..91979ec 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -353,6 +353,9 @@ function toRetry(err) {
   };
 }
 
+/**
+ * Retries only work on critical HTTP 5XX errors
+ */
 function retry(fn, ctx) {
   ctx.retryAttempts = [];
   const maxAttempts = ctx.retries;
@@ -360,7 +363,7 @@ function retry(fn, ctx) {
   function attempt(i) {
     return fn(ctx)
       .catch((err) => {
-        if (maxAttempts > 0) {
+        if (i < maxAttempts && isCriticalError(err) && ctx.retryDelay && ctx.retryDelay > 0) {
           const delayBy = rejectedPromise(ctx.retryDelay);
           return delayBy(err);
         }
diff --git a/lib/context.js b/lib/context.js
index 3d2be15..110d668 100644
--- a/lib/context.js
+++ b/lib/context.js
@@ -10,6 +10,9 @@ const USER_AGENT = `${packageInfo.name}/${packageInfo.version}`;
 
 class Context {
   constructor(defaults) {
+    /**
+     * Retries only work on critical HTTP 5XX errors
+     */
     this.retries = 0;
     this.redirect = undefined;
     this._retryAttempts = [];